JP2017050086A - Lighting device, lighting control ic, and illumination device - Google Patents

Abstract

An analog / digital composite lighting control IC improved for reducing the number of parts of a lighting device, and a lighting device and a lighting device including the same are provided. A lighting device includes a switching power supply circuit for lighting that generates a DC power source using a switching element and lights a light source with the DC power source, and a lighting control IC that controls the switching power supply circuit for lighting. . The lighting control IC includes a digital chip portion provided with a digital arithmetic circuit that performs an operation for controlling the switching power supply circuit for lighting, a drive circuit that drives the switching element, the digital arithmetic circuit, and the drive circuit And an analog chip portion provided with at least part of a control power supply switching power supply circuit for generating a control power supply in a single package. [Selection] Figure 1

Description

  The present invention relates to a lighting device, a lighting control IC, and a lighting device.

  Conventionally, for example, as disclosed in Patent Document 1 below, a step-up chopper circuit (so-called PFC circuit) having a power factor improving function and a DC-DC converter (so-called buck converter) that steps down the output voltage of the PFC circuit And a lighting device for lighting the LED module is known. Further, in the lighting device for a fluorescent lamp disclosed in Patent Document 2 below, the control circuit for the boost chopper circuit and the control circuit for the inverter circuit are provided as one integrated circuit.

JP 2007-202285 A Japanese Patent No. 4460202

  In recent years, lighting fixtures using solid-state light-emitting elements instead of conventional light sources such as fluorescent lamps have become widespread, and techniques for digitizing the lighting control have been developed. In this regard, the inventor of the present application has been diligently researching based on a novel idea of making a lighting control IC for a lighting fixture into an analog / digital composite IC package. On the other hand, there is also a demand to reduce the number of parts of the lighting device, more specifically, the number of components mounted on the circuit board of the lighting device as much as possible.

  The present invention has been made to solve the above-described problems, and is an analog / digital combined lighting control IC improved from the viewpoint of reducing the number of parts of the lighting device, and a lighting device and an illumination including the same. An object is to provide an apparatus.

  A lighting device according to a first aspect of the present invention is a lighting switching power supply circuit that generates a DC power supply using a switching element and lights a light source with the DC power supply, a lighting control IC that controls the switching power supply circuit for lighting, The lighting control IC includes a digital chip portion provided with a digital arithmetic circuit that performs an operation for controlling the switching power supply circuit for lighting, a drive circuit that drives the switching element, the digital arithmetic circuit, and An analog chip unit provided with at least a part of a control power circuit unit that generates power for the drive circuit is housed in one package.

  A lighting device according to a second aspect of the present invention is a lighting switching power supply circuit that generates a DC power source using a switching element and lights a light source with the DC power source, a lighting control IC that controls the switching power supply circuit for lighting, A capacitor provided inside or outside the lighting control IC, charged with the electric energy output from the switching power supply circuit for lighting, and a stored charge used as a power source for the lighting control IC, The lighting control IC includes a digital chip portion provided with a digital arithmetic circuit that performs a calculation for controlling the switching power supply circuit for lighting, and an analog chip portion provided with a drive circuit that drives the switching element. The digital arithmetic circuit is configured to turn off the light source. The lighting switching power supply circuit as a predetermined control power supply voltage to the capacitor in the machine mode is applied and executes the calculation processing for the constant voltage control.

  A lighting control IC according to a third aspect of the present invention is a lighting control IC that generates a DC power source using a switching element and controls a lighting switching power supply circuit that lights a light source with the DC power source. A digital chip portion provided with a digital arithmetic circuit that performs an operation for controlling the switching power supply circuit for lighting, a drive circuit that drives the switching element, and a control power supply that generates power for the digital arithmetic circuit and the drive circuit An analog chip part provided with at least a part of a circuit part is housed in one package.

  A lighting control IC according to a fourth aspect of the present invention is a lighting control IC that generates a DC power source using a switching element and controls a lighting switching power source circuit that lights a light source with the DC power source. A digital chip part provided with a digital arithmetic circuit for performing an operation for controlling the switching power supply circuit for lighting, and an analog chip part provided with a drive circuit for driving the switching element in one package The digital arithmetic circuit is less than the voltage at which the light source is turned on in the standby mode after the light source is turned off, and the higher voltage value of the power supply voltage of the digital arithmetic circuit and the power supply voltage of the drive circuit An arithmetic process for constant voltage control of the output voltage value of the lighting switching power supply circuit so as to become the above Row.

  An illuminating device according to a fifth aspect of the present invention includes the lighting device according to the first or second aspect of the present invention, and the light source module configured of the solid light emitting element is turned on by the lighting device.

  According to the first aspect of the present invention, a novel configuration is adopted in which at least a part of the control power supply circuit unit used for generating the control power supply is integrated into the analog / digital composite IC package. Thereby, the number of parts to be mounted on the lighting device can be reduced.

  According to the second aspect of the invention, a novel configuration is adopted in which the arithmetic processing related to the generation of the control power supply is integrated into the digital arithmetic circuit in the analog / digital composite IC package. Thereby, the number of parts to be mounted on the lighting device can be reduced.

  According to the third aspect of the invention, a novel configuration is adopted in which at least a part of the control power supply circuit unit used for generating the control power supply is integrated into the analog / digital composite IC package. Thereby, the number of parts to be mounted on the lighting device can be reduced. Since the active elements inside the package and the passive elements and capacitors outside the package can be connected via the terminals, a power supply circuit for generating a control power supply can be configured using these. The electric charge stored in the capacitor can be used as a control power source that is a power source of the lighting control IC.

  According to the fourth invention, in the analog / digital composite IC package, a new configuration is adopted in which the arithmetic processing relating to the generation of the control power supply is integrated into the digital arithmetic circuit. Thereby, the number of parts to be mounted on the lighting device can be reduced. Since the arithmetic processing for generating the control power by constant voltage control is executed by the digital arithmetic circuit while the light source is turned off, the control power can be stably supplied even when the light source is turned off.

  According to the fifth aspect, the provision of the lighting device with a reduced number of components leads to a reduction in the number of components as the entire lighting device.

It is a circuit block diagram showing the lighting device concerning Embodiment 1 and a lighting fixture provided with the same. 1 is a diagram illustrating a schematic configuration of a lighting device according to a first embodiment. FIG. 3 is a diagram illustrating a schematic configuration of a lighting control IC according to the first embodiment. FIG. 6 is a block configuration diagram illustrating a schematic configuration of a modification of the lighting control IC according to the first embodiment. FIG. 6 is a diagram illustrating a schematic configuration of a lighting device according to a modification of the first embodiment. FIG. 10 is a diagram illustrating a schematic configuration of a modification of the lighting control IC according to the first embodiment. FIG. 6 is a diagram illustrating a schematic configuration of a lighting device according to a modification of the first embodiment. FIG. 10 is a diagram illustrating a schematic configuration of a modification of the lighting control IC according to the first embodiment. FIG. 6 is a diagram illustrating a schematic configuration of a lighting device according to a modification of the first embodiment. FIG. 10 is a diagram illustrating a schematic configuration of a modification of the lighting control IC according to the first embodiment. FIG. 6 is a diagram illustrating a schematic configuration of a lighting device according to a modification of the first embodiment. FIG. 10 is a diagram illustrating a schematic configuration of a modification of the lighting control IC according to the first embodiment. It is a circuit block diagram showing the lighting device concerning the modification of Embodiment 1, and a lighting fixture provided with the same. It is a figure showing the typical structure of the lighting device concerning the comparative example with respect to embodiment. It is a circuit block diagram showing the lighting device concerning Embodiment 2 and a lighting fixture provided with the same. FIG. 6 is a diagram illustrating a schematic configuration of a lighting device according to a second embodiment. FIG. 6 is a diagram illustrating a schematic configuration of a lighting control IC according to a second embodiment. It is a circuit block diagram showing the lighting device concerning the 1st modification of Embodiment 2, and a lighting fixture provided with the same. It is a circuit block diagram showing the lighting device concerning the 2nd modification of Embodiment 2, and a lighting fixture provided with the same. It is a circuit block diagram showing the lighting device concerning Embodiment 3, and a lighting fixture provided with the same. It is a perspective view of the lighting fixture concerning Embodiment 3. FIG. It is a circuit block diagram of the other lighting fixture concerning Embodiment 3. FIG.

  Hereinafter, embodiments of the invention disclosed in the present application will be described with reference to the drawings. The following embodiment relates to a lighting device including a switching power supply circuit that generates a DC power supply using a switching element, and a lighting control IC that controls the switching power supply circuit. The lighting control IC according to the following embodiment includes a digital chip portion provided with a digital arithmetic circuit and an analog chip portion provided with a drive circuit for driving the switching element in one package. In common. That is, the basic lighting control IC provided in common in the embodiment is an analog-digital composite IC package. In the following embodiment, a plurality of improved concepts for the basic lighting control IC are provided. The plurality of improvement concepts can be implemented independently from each other, but the plurality of improvement concepts can be applied to one lighting control IC at the same time.

  Specifically, the first improved lighting control IC disclosed in the present application is “at least a part of the control power supply circuit unit”, specifically, at least a part of the control power supply switching circuit (as a specific example, An active element such as a transistor constituting a control power source) is incorporated in the above basic lighting control IC, and the first embodiment relates to this. The second improved lighting control IC disclosed in the present application is such that the microcomputer executes a calculation process for generating a control power source by software control in the above basic lighting control IC. It is about. A third improved lighting control IC disclosed in the present application is the above basic lighting control IC provided with a “digital communication terminal” connected to an external optional device by a microcomputer. Is about this. The third improved lighting control IC can be combined with the first or second improved lighting control IC described above.

[Apparatus Configuration According to First Embodiment]
FIG. 1 is a circuit block diagram illustrating a lighting device 150 and a lighting fixture including the lighting device 150 according to the first embodiment. The lighting device 150 includes an input filter rectification unit 100 connected to the commercial power supply 5, a lighting switching power supply circuit 250 that receives DC power from the input filter rectification unit 100 (hereinafter also referred to as “lighting SW power supply circuit 250”). A lighting control IC 700 that controls the lighting SW power supply circuit 250, a control power switching power supply circuit 500 that generates control power for the lighting control IC 700 (hereinafter also referred to as “control power SW power circuit 500”), An external interface 620 such as a connector that mediates electrical connection between the resistors 16 to 40 and the capacitors 24 to 70 provided around the control IC (integrated circuit) 700 and the lighting control IC 700 and an external device (that is, an additional unit). And. The lighting SW power supply circuit 250 generates DC power using the switching elements 12 and 31 that are MOSFETs, and lights the light source module 400 with the DC power.

  The input filter rectifier 100 includes an input filter circuit 110 that receives AC power from the commercial power supply 5, and a rectifier circuit that is connected to the subsequent stage of the input filter circuit 110. The rectifier circuit is a diode bridge composed of diodes 1 to 4, and the rectified DC voltage is input to the lighting SW power supply circuit 250.

  The lighting SW power supply circuit 250 steps down a DC voltage supplied from the power factor correction circuit 200 (hereinafter also simply referred to as “PFC (power factor correction) circuit 200”) connected to the input filter rectifier 100 and the PFC circuit 200. And a buck converter circuit 300. PFC circuit 200 is a step-up chopper circuit including choke coil 11, switching element 12, diode 13, and capacitor 14 in the first embodiment. The source of the switching element 12 is connected to the ground terminal Gm via the resistor 15. However, other than the step-up chopper circuit, for example, a flyback circuit may be used. The buck converter circuit 300 steps down the DC voltage output from the PFC circuit 200 and is controlled to supply a constant DC current to the light source module 400. Buck converter circuit 300 is a step-down chopper circuit including switching element 31, choke coil 33, diode 32, and capacitor 34. The buck converter circuit 300 is provided with a detection resistor 35 that outputs a voltage corresponding to the LED current. One end of the detection resistor 35 is connected to the anode of the diode 32, and the other end of the detection resistor 35 is connected to the negative electrode of the capacitor 34.

  In the light source module 400, a plurality of solid state light emitting devices 60 to 63 are mounted on a mounting board (not shown). As the solid-state light emitting element, an inorganic LED element or an organic EL element (also referred to as OLED) can be used. In FIG. 1, the solid light emitting elements 60 to 63 are connected in series as an example, but the connection method may be parallel or series-parallel connection, and the number of solid light emitting elements may be arbitrarily changed.

  The control power supply SW power supply circuit 500 includes a control power supply IC unit 510 incorporating a switching element and the like, a control power supply circuit 520 that forms a step-down chopper circuit together with the switching element of the control power supply IC unit 510, capacitors 50 and 70, It has. The control power SW power supply circuit 500 is a step-down converter circuit that generates a control power supply by a chopper operation of a switching element built in the control power supply IC unit 510. The power output from the PFC circuit 200 is input to the control power supply IC unit 510. Using this power, control power supply IC unit 510 and control power supply circuit 520 generate a control power supply voltage of 10 to 20 V, for example, 15 V as an example, and capacitors 50 and 70 are charged with this voltage. The electric charge stored in the capacitors 50 and 70 is supplied to each circuit provided inside the lighting control IC 700 as a control power source.

  The lighting control IC 700 includes a PFC control circuit 210, a buck converter control circuit 310, a microcomputer 610 (hereinafter also simply referred to as “microcomputer 610”), a control power supply IC unit 510, as indicated by a thick line frame in FIG. Is included.

  FIG. 2 is a diagram illustrating a schematic configuration of the lighting device 150 according to the first embodiment. FIG. 2 shows a lighting device 150 having a long outer shape as an example of the device configuration. Each circuit is provided on a long printed circuit board 900 shown in FIG. FIG. 3 is a diagram illustrating a schematic configuration of the lighting control IC 700 according to the first embodiment. The lighting control IC 700 is one in which two chips are housed in an IC package. The two chips are an analog chip 701 and a digital chip 702, and the circuits formed in each of them form an integrated lighting control IC 700. For convenience, the digital chip 702 and the analog chip 701 are not shown in FIGS. 1-2, but are shown in FIG.

  The analog chip 701 is provided with a PFC control circuit 210 and a buck converter control circuit 310. PFC control circuit 210 and buck converter control circuit 310 include drive circuits that drive switching elements 12 and 31, respectively. Further, the analog chip 701 is provided with at least a part of the control power SW power supply circuit 500 shown in FIG. In the first embodiment, as a specific example, the control power supply IC unit 510 of the control power supply SW power supply circuit 500 is provided in the analog chip 701 as described later. The configuration other than the control power supply IC unit 510 in the control power supply SW power supply circuit 500 is the printed circuit board 900 on which various components of the lighting device 150 are mounted outside the IC package of the lighting control IC 700 (see FIG. 2). It is provided above.

  The lighting control IC 700 is obtained by storing an analog chip 701 and a digital chip 702 in “one IC package”. In the embodiment, the state of being housed in one IC package means that the components of the IC are covered with a common sealing resin or housed in a single case, so that they can be placed on a circuit board or the like as a single component. It indicates a state where it can be implemented. These sealing resin bodies and cases are sometimes collectively referred to as “enclosures”.

  1 to 3 show grounds Gm to Gc. The ground Gm is a common ground for the input filter rectifier 100, the lighting SW power circuit 250, and the light source module 400. The ground Gp is the ground of the PFC control circuit 210. The ground Gb is a ground for the buck converter control circuit 310. The ground Gv is a ground of the control power supply IC unit 510 constituting the control power supply SW power supply circuit 500. The ground Gc is the ground of the microcomputer 610.

  Details of the circuit configuration will be described with reference to FIG. The PFC control circuit 210 receives a first drive circuit that outputs a gate signal to the gate of the MOFET 12 via the resistor 21 and a divided voltage value obtained by dividing the cathode voltage of the diode 13 by the resistors 22 and 25. A first voltage detection circuit; a first current detection circuit to which a voltage generated in the resistor 15 is input via the resistor 23; and a zero cross detection circuit for detecting that the current of the choke coil 11 becomes zero via the resistor 18. A multiplier for detecting a pulsating voltage divided value; a first control power electrode connected to the positive electrode of the capacitor 50 for receiving a control power; and a first for stopping a circuit operation when receiving a predetermined stop signal. A stop circuit and a first ground electrode for obtaining a circuit reference potential (ground Gp) of each of the above circuits are provided. Each of the above circuits is an analog circuit constructed on an analog chip 701 unlike the microcomputer 610 which is a digital circuit. The pulsating voltage divided value detected by the multiplier is a value obtained by dividing the pulsating voltage input from the input filter rectifying unit 100 to the input terminal of the choke coil 11 by the resistors 16 and 17. In association with the PFC control circuit 210, capacitors 24 to 26 are provided around the lighting control IC 700. The resistor 17 is connected in parallel to the capacitor 27. The resistor 25 is connected to the capacitor 26 in parallel. One end of the capacitor 41 is connected to a connection point between the control power supply electrode and the capacitor 50, and the other end of the capacitor 41 is connected to the ground Gb.

  The buck converter control circuit 310 includes a second drive circuit that outputs a gate signal to the gate of the switching element 31 via the gate resistor 36 according to an operation target value from the microcomputer 610, and a current detection that occurs in the resistor 35 according to the LED current. A second current detection circuit in which a voltage is input through a resistor 37, a second stop circuit for stopping circuit operation when a predetermined stop signal is received, and an operation target value received from the microcomputer 610 are transmitted to the drive circuit An operation target input unit, a second control power electrode connected to the positive electrode of the capacitor 50 to receive the control power, and a second ground electrode for obtaining a circuit reference potential (ground Gb) of each circuit. ing. Each of the above circuits is an analog circuit constructed in an analog chip 701, unlike the microcomputer 610 which is a digital circuit. In connection with the back converter control circuit 310, several passive elements are provided around the lighting control IC 700. That is, one end of the resistor 37 is connected to the connection point between the resistor 35 and the cathode end of the light source module 400, and the voltage at the connection point between the other end of the resistor 37 and one end of the capacitor 38 is input to the second current detection circuit. The other end of the capacitor 38 is connected to the ground Gb. One end of the capacitor 41 is connected to the connection point between the second control power supply electrode and the capacitor 50, and the other end of the capacitor 41 is connected to the ground Gb.

  In the control power supply SW power supply circuit 500, the control power supply IC unit 510 is housed in the IC package, while the control power supply circuit 520 and the capacitors 50 and 70 are provided outside the IC package. The control power supply IC unit 510 includes transistors and diodes, and these transistors and diodes are active elements constituting the control power supply SW power supply circuit 500, that is, active elements constituting the step-down chopper circuit. On the other hand, the control power supply circuit 520 is specifically provided with a choke coil as a passive element constituting the control power supply SW power supply circuit 500. A step-down chopper circuit is configured by the choke coil and an active element such as a transistor included in the control power supply IC unit 510. Capacitors 50 and 70 charged by the step-down chopper circuit are provided outside the IC package.

  The digital chip 702 is provided with a microcomputer 610. The microcomputer 610 controls the PFC control circuit 210 and the buck converter control circuit 310 based on a command signal input from the external interface 620. For example, a dimming signal is input to the external interface 620 from a dimmer (not shown). A divided voltage value obtained by dividing the load voltage of the light source module 400 by the resistors 39 and 40 is also input to the microcomputer 610. The microcomputer 610 includes an arithmetic processing unit, a memory, and the like, and can store and execute various digital information and control programs necessary for lighting control. As a specific example of control, the microcomputer 610 outputs an operation target value related to switching control of the switching elements 12 and 31. If the lighting device 150 performs dimming control, a dimming signal is transmitted from the external interface 620 to the microcomputer 610, and the microcomputer 610 is turned on for lighting the light source module 400 at a dimming rate according to the dimming signal. The duty is calculated and output as an operation target value. Further, the microcomputer 610 outputs a stop signal to the stop circuit of each of the PFC control circuit 210 and the buck converter control circuit 310, for example, when detecting an overvoltage state in which the load voltage has become a predetermined value or more. As a result, during the abnormal operation of the lighting SW power supply circuit 250, a protective operation such as stopping the switching elements 12 and 31 is performed.

  Instead of the microcomputer 610, a digital signal processor (Digital Signal Processor: DSP) may be formed on the digital chip 702 and housed in the IC package of the lighting control IC 700. In any case, the digital chip 702 is provided with a “digital arithmetic circuit” such as a microcomputer or a DSP, and this digital arithmetic circuit performs arithmetic processing related to lighting control of the lighting SW power supply circuit 250. In the first embodiment, one microcomputer 610 is illustrated and described. However, the number of digital chips mounted on a digital arithmetic circuit such as a microcomputer and a DSP may be two or more. The digital chip 702 may be constructed so as to perform lighting control in cooperation.

  The lighting control IC 700 according to the first embodiment includes a control power supply IC unit 510 in one IC package in addition to the PFC control circuit 210, the back converter control circuit 310, and the microcomputer 610. As described above, by integrating at least a part of the control power SW power supply circuit 500 constituting the control power supply into the analog / digital composite IC package, the number of parts constituting the lighting device 150 can be reduced.

  Further, according to the first embodiment, the lighting SW power supply circuit 250 is a two-converter type, and the drive circuit relating to driving of each converter is housed in one IC package. Thereby, compared with the case where the drive circuit etc. of each converter are stored in a separate IC package, the number of parts of the lighting device 150 can be reduced.

  In the first embodiment, only the control power IC unit 510 of the control power SW power supply circuit 500 is housed in the IC package of the lighting control IC 700. However, the control power supply circuit 520 and the capacitors 50 and 70 may not be placed outside the IC package, and any or all of them may be further housed in the IC package. That is, the lighting control IC 700 may be one in which the entire control power supply SW power supply circuit 500 is housed in an IC package.

[Common use of ground wiring / feeding wiring]
In addition to the above-described feature of “one package of the PFC control circuit 210, the back converter control circuit 310, the microcomputer 610, and the control power supply IC unit 510”, the lighting control IC 700 has a ground wiring and / or a control power supply wiring. Also has features. Hereinafter, electrical connection patterns of “ground wiring” and “feed wiring” according to the first embodiment will be described. The “ground wiring” connects the grounds (i.e., four grounds Gp to Gc) of each circuit built in the lighting control IC 700 inside and outside the IC package of the lighting control IC 700. That is, the ground wiring is a conductor pattern including a wiring pattern and an electrode pattern that should be set to the ground potential when the lighting device 150 and the lighting control IC 700 are operated. The ground wiring is divided into “internal ground wiring” provided inside the IC package and “external ground wiring” provided outside the IC package. The “power supply wiring” is a wiring for supplying control power to each circuit inside and outside the IC package of the lighting control IC 700, and includes a wiring formed on the substrate and a power supply electrode. The power supply wiring is also divided into “internal power supply wiring” provided inside the IC package and “external power supply wiring” provided outside the IC package.

(Electrical connection pattern according to the first embodiment)
2 and 3, the lighting control IC 700 shown in FIGS. 2 and 3 includes internal ground wirings 720 and 721 and internal power supply wirings 722 and 723. In addition, an external ground wiring 720 c and an external power supply wiring 735 are provided around the lighting control IC 700.

  First, the electrical connection pattern of the ground wiring will be described. The lighting control IC 700 includes ground terminals 731 and 733. One end of each of the ground terminals 731 and 733 is exposed to the outside of the IC package, and the other end is connected to the internal ground wirings 720 and 721 inside the IC package. Further, the external ground wiring 720c is connected to the ground terminals 731 and 733 outside the IC package.

  The internal ground wiring 720 is connected to the ground Gp of the PFC control circuit 210 and the ground Gb of the buck converter control circuit 310 inside the IC package, and these grounds are shared. The internal ground wiring 721 is connected to the ground Gv of the control power supply IC unit 510 and the ground Gc of the microcomputer 610 inside the IC package, and these grounds are shared.

  The circuit connected to the internal ground wiring 720 and the circuit connected to the internal ground wiring 721 are once detoured by the external ground wiring 720c outside the IC package and then connected to the ground wiring. That is, the distance between the circuit connected to the internal ground wiring 720 and the circuit connected to the internal ground wiring 721 can be increased. For this reason, the mutual influence of the circuit operation due to noise or the like can be reduced. The external ground wiring 720c is preferably a conductor pattern (so-called solid pattern) that is thicker and shorter than wirings such as other signal lines, communication lines, and electric wires.

  In the example of FIG. 3, the lighting control IC 700 has a rectangular shape, and a plurality of terminals are arranged on two long sides of the four sides. Note that the number of terminals is a schematic one. More than three. In the example of FIG. 3, ground terminals 731 and 733 are provided one by one on the opposite two sides of the four sides of the lighting control IC 700. However, the ground terminals 731 and 733 may be combined into the same one of the four sides of the lighting control IC 700, and the ground terminals 731 and 733 may be arranged adjacent to each other. The adjacent arrangement is to arrange them adjacent to each other without including other terminals. As a result, the external ground wiring 720c can be easily formed into a thick and short large-area conductor pattern (so-called solid pattern), and the ground can be stabilized. This also applies to the modified examples described below.

  Next, the electrical connection patterns of the control power supply terminals 732 and 734 and the power supply wiring will be described. The lighting control IC 700 includes control power supply terminals 732 and 734 and internal power supply wirings 722 and 723. One end of the control power supply terminal 732 is exposed outside the IC package and is connected to the positive electrode of the capacitor 50 to receive control power. Similarly, one end of the control power supply terminal 734 is exposed to the outside of the IC package and is connected to the positive electrode of the capacitor 70 to receive control power. The external power supply wiring 735 connects the control power supply terminal 732 and the control power supply terminal 734 outside the IC package.

  The internal power supply wiring 722 supplies control power to the PFC control circuit 210 and the back converter control circuit 310 inside the IC package. On the other hand, the internal power supply wiring 723 supplies control power to the control power IC unit 510 and the microcomputer 610 inside the IC package.

  A regulator 522 is connected to the internal power supply wiring 723. The regulator 522 steps down the first control power supply voltage (for example, 15V) extracted from the capacitor 50 to a second control power supply voltage (for example, 5V) lower than this. In other words, the regulator 522 converts the voltage supplied to the analog circuit provided in the analog chip 701 and supplies the converted voltage to the digital circuit provided in the digital chip 702. The regulator 522 can generate a digital circuit power supply from an analog circuit power supply.

  As for the internal power supply wiring 723, the internal power supply wiring 723 includes a “merging wiring portion” connected to the control power supply terminal 732 and a “branching wiring portion” in which the joining wiring portion branches in the middle. . One of the branch wiring portions is connected to the regulator 522, and the microcomputer 610 is connected to the subsequent stage of the regulator 522. The other one of the branch wiring units is connected to the control power supply IC unit 510 and supplies the voltage 15V of the control power supply terminal 732 to the control power supply IC unit 510 as it is.

  In the circuit connected to the internal power supply wiring 722 and the circuit connected to the internal power supply wiring 723, the control power is supplied from the separate capacitors 50 and 70, so that the distance on the power supply wiring can be increased. That is, the control power supply wiring can be separated from each other, and the mutual influence of the circuit operation can be reduced.

(Comparative example for the embodiment)
FIG. 14 is a diagram illustrating a schematic configuration of a lighting device according to a comparative example with respect to the embodiment. In FIG. 14, as a comparative example, the circuit of FIGS. 1 to 3 is modified to include four IC packages. In FIG. 14, a PFC control circuit 210, a buck converter control circuit 310, a control power supply IC unit 510, and a microcomputer 610 are provided as separate IC packages. In general, it is advantageous from the viewpoint of reducing noise influence that the control circuit and the microcomputer can be arranged close to the control power supply circuit on the mounting circuit board on which the components of the lighting device are mounted. However, if a plurality of IC packages are scattered on the mounting circuit board, the power supply wiring and the ground wiring that connect them are likely to be complicated, and particularly the ground wiring inhibits ground stabilization. In particular, when the entire board is elongated like the printed circuit board 900, the power supply wiring and the ground wiring must be routed very long in the longitudinal direction of the mounting circuit board as shown in FIG. Absent.

  In this regard, according to the lighting control IC 700 according to the first embodiment described above, the PFC control circuit 210, the back converter control circuit 310, the microcomputer 610, and the control power supply IC unit 510 are housed in one IC package. These ground wiring and power supply wiring are shared. As a result, the ground wiring and the power supply wiring can be dramatically stabilized, simplified, and made efficient.

(Electrical connection pattern according to a modification of the first embodiment)
4 to 12 are block configuration diagrams illustrating schematic configurations of modified examples of the lighting control IC 700 according to the first embodiment. 5, FIG. 7, FIG. 9, and FIG. 11 are diagrams illustrating a schematic configuration of a modified example of the lighting device 150 according to the first embodiment. 4, 6, 8, 10, and 12 are diagrams illustrating a schematic configuration of a modified example of the lighting control IC 700 according to the first embodiment.

  In the first modification shown in FIG. 4, the capacitor 50 is omitted, and the control power source of the lighting control IC 700 is taken out only from the capacitor 70. The lighting control IC 700 has a power supply wiring 722a. The power supply wiring 722a connects the other end of the control power supply terminal 734 to the analog chip 701 and the digital chip 702 inside the IC package, and supplies control power to both the analog chip 701 and the digital chip 702. However, the regulator 522 provided in the analog chip 701 drops the voltage (for example, 15V) and supplies 5V to the microcomputer 610, similar to the lighting control IC 700 shown in FIG.

  Since the power supply wiring of the control power supply can be made common within the IC package, the power supply wiring can be shortened as compared with the case where one package is not used (comparative example in FIG. 14). Further, the control power supply potential is unified by covering the control power supply inside the lighting control IC 700 with one power supply wiring 722a. As a result, the circuit operation can be stabilized.

  The internal power supply wiring 722a will be further described. The internal power supply wiring 722a includes a “merging wiring portion” connected to the control power supply terminal 734 and a “branch wiring portion” in which the joining wiring portion branches in the middle. The plurality of branch wiring units are connected to the PFC control circuit 210, the buck converter control circuit 310, and the control power supply IC unit 510 one by one. Another one of the branch wiring portions is connected to the regulator 522, and the microcomputer 610 is connected to the subsequent stage of the regulator 522. Thus, a plurality of branch wiring portions are provided by branching the power supply wiring 722a inside the IC package. Since the distance on the power supply wiring can be increased between circuits connected to different branch wiring parts, the mutual influence of circuit operation can be reduced between circuits connected to different branch wiring parts.

  As a further modification, the ground may be completely divided between the analog circuit and the digital circuit in the IC package. The internal ground wiring 720 may share the ground of all circuits included in the analog chip 701, and the internal ground wiring 721 may share the ground of all circuits included in the digital chip 702. These internal ground wirings 720 and 721 may be connected to separate ground terminals 731 and 733 and connected outside the IC package via the external ground wiring 720c. When this modification is added, it is possible to further reduce the influence of the switching noise generated in the analog circuit on the digital circuit, and it is possible to effectively suppress the malfunction of the microcomputer due to the noise or the like.

  In the second modified example shown in FIGS. 5 and 6, the PFC control circuit 210, the back converter control circuit 310, the control power supply IC unit 510, and the microcomputer 610 are combined into one group in the IC package of the lighting control IC 700. Both ground wiring and power supply wiring are shared. The lighting control IC 700 includes an internal ground wiring 724 connected to the ground terminal 731. The internal ground wiring 724 is connected to all of the grounds Gp, Gb, Gv, and Gc through a plurality of branch wiring portions, and is connected to the ground terminal 731 at the junction wiring portion while making them common. Since the ground can be shared in the IC package, the ground wiring can be shortened and the influence of noise can be suppressed as compared with the case where one package is not used (comparative example in FIG. 14). The circuit reference potential is also unified. As a result, the circuit operation can be stabilized. In addition, the lighting control IC 700 includes an internal power supply wiring 726 connected to the control power supply terminal 732. The internal power supply wiring 726 is similar to the internal power supply wiring 722a in that it branches from one control power supply terminal 732 and supplies control power to a plurality of circuits, and further includes a regulator 522 in one of the branch wiring sections. .

  7 to 10, in the IC package of the lighting control IC 700, the PFC control circuit 210, the back converter control circuit 310, the control power supply IC unit 510, and the microcomputer 610 are combined into one group, and ground wiring is provided. The control power supply wiring is integrated into one. The circuit configuration of the power supply wiring in FIGS. 7 to 10 is the same as that described in FIG. For this reason, the modification shown in FIGS. 7 to 10 has one ground terminal and one control power supply terminal.

  In the third modification shown in FIGS. 7 and 8, the lighting control IC 700 includes an internal power supply wiring 726 and an internal ground wiring 727. The internal ground wiring 727 includes a junction wiring portion (not labeled) connected to the other end of the ground terminal 731 and a plurality of branch wiring portions 727a and 727b branched from the junction wiring portion. The ground lines Gp to Gv are connected to the branch wiring part 727a. A ground Gc is connected to the branch wiring portion 727b.

  Since the plurality of branch wiring portions 727a and 727b are provided by branching the common ground wiring inside the IC package, the distance on the ground wiring can be increased between circuits connected to the different branch wiring portions 727a and 727b. In the circuits connected to the different branch wiring portions 727a and 727b, the mutual influence of the circuit operation can be reduced. In particular, in the modification shown in FIGS. 7 and 8, the circuit of the analog chip 701 is combined in the branch wiring portion 727a, and the circuit of the digital chip 702 is connected to the branch wiring portion 727b. By connecting the analog circuit and the digital circuit to separate branch wiring portions in this way, it is possible to make it difficult for the digital circuit to be affected by switching noise generated in the analog circuit. Therefore, malfunction of the microcomputer due to noise can be reliably suppressed.

  9 and 10, the lighting control IC 700 includes an internal power supply wiring 726 and an internal ground wiring 728. Internal ground wiring 728 includes a junction wiring portion (not labeled) connected to the other end of ground terminal 731 and a plurality of branch wiring portions 728a and 728b branched from the junction wiring portion. Grounds Gp and Gb are connected to the branch wiring part 728a. On the other hand, the ground lines Gv and Gc are connected to the branch wiring portion 728b. By connecting the grounds Gp and Gb to a branch wiring part different from the grounds Gc and Gv, they can be separated in an electrical sense. Thereby, it is possible to suppress the switching noise of the drive circuits included in the PFC control circuit 210 and the buck converter control circuit 310 from being transmitted to the microcomputer 610 and the control power supply IC unit 510.

  In the fifth modification shown in FIGS. 11 and 12, the lighting control IC 700 includes an internal power supply wiring 726 and internal ground wirings 729a and 729b. The internal ground wiring 729 b connects the other end of the ground terminal 731 to the ground Gc of the microcomputer 610. On the other hand, the internal ground wiring 729a includes a junction wiring portion connected to the ground terminal 733 and a plurality of branch wiring portions branched from the junction wiring portion. The branch wiring portions are connected to the grounds Gp, Gb, and Gv, respectively. In this case, the ground terminal is divided between the analog chip 701 and the digital chip 702. The ground terminal 731 and the ground terminal 733 are connected outside the IC package via an external ground wiring 720c.

  FIG. 13 is a circuit block diagram illustrating a lighting device 151 according to a modified example (sixth modified example) of the first embodiment and a lighting fixture including the same. In the lighting device 151, the overall lighting control is performed by digital control. Such a lighting device is also called a full digital power supply device. The lighting device 151 according to the sixth modification has the lighting device shown in FIG. 1 except that the lighting SW power circuit 250 is replaced with a lighting SW power circuit 251 and the lighting control IC 700 is replaced with a lighting control IC 760. The same circuit configuration as that of 150 is provided. Therefore, in the following description, the same or corresponding components as those in the first embodiment will be described with the same reference numerals, and differences from the first embodiment will be mainly described, and common items will be briefly described. Or omitted.

  The lighting SW power supply circuit 251 is obtained by replacing the PFC circuit 200 with the PFC circuit 201 and replacing the back converter circuit 300 with the back converter circuit 301. The PFC circuit 201 is obtained by adding a secondary winding 11a to the choke coil 11 of the PFC circuit 200 of FIG. The buck converter circuit 301 is obtained by adding a secondary winding 33a to the choke coil 33 of the buck converter circuit 300 of FIG. The lighting control IC 760 is different from the lighting control IC 700 of FIG. 1 in that “functions other than the drive circuit” in the PFC control circuit 210 and the back converter control circuit 310 shown in FIG. . The analog chip 761 included in the lighting control IC 760 is provided with a drive circuit 764 and a control power supply IC unit 510. A microcomputer 710 is formed in the digital chip 762 included in the lighting control IC 760.

  The drive circuit 764 and the microcomputer 710 are connected to a common ground via an internal ground wiring 770. The internal ground wiring 770 is connected to the GND1 (SIG) terminal. Although not shown, in the sixth modification, the ground of the control power supply IC unit 510 is also connected to the GND1 (SIG) terminal, and the internal ground wiring branched from one ground terminal (GND1 (SIG) terminal) is driven. It is assumed that the circuit 764, the microcomputer 710, and the control power supply IC unit 510 are connected. Further, the supply of control power will be described. First, the control power supply voltage (for example, 15 V) obtained from the capacitor 50 via the Vcc1 terminal which is the control power supply terminal is connected to the first internal power supply wiring not shown in FIG. Via the drive circuit 764 and the control power supply IC unit 510. Further, a control power supply voltage of, for example, 15V applied to the Vcc1 terminal which is a control power supply terminal is stepped down to, for example, 5V by the regulator 522, and the voltage after the step-down is supplied to the microcomputer 710 via a second internal power supply wiring (not shown). Is done. Various modifications can be made to the ground wiring and the power supply wiring included in the lighting device 151 of FIG. As described in the first embodiment and the second to fifth modifications (see FIGS. 1 to 12), a plurality of ground terminals / control power supply terminals are connected by external ground wiring / external power supply wiring. The branching method of internal ground wiring / internal power supply wiring and circuit grouping may be variously modified.

  The circuit configuration of the control power supply IC unit 510 is shown in more detail than FIG. Specifically, the control power supply IC unit 510 includes a constant current circuit 766, diodes D1, D2, D10, and D11, and a constant voltage generation circuit unit 511 (for example, IPD: intelligent Power device). The constant current circuit 766 acquires the output power of the PFC circuit 201 via the PFCV terminal, generates a constant current from the acquired power, and charges the bootstrap capacitor CBS through the diode D10 and the VB terminal with the constant current. A Zener diode Dz1 is connected in parallel to the bootstrap capacitor CBS. The PFCV terminal can also be called a CP terminal in the sense that it is a terminal for charge pumping.

  The microcomputer 710 is connected to the analog chip 761 via the wirings W1 to W6. The wiring W1 is a path for reducing the output voltage of the PFC circuit 201 by resistance division and detecting it by the microcomputer 710. The wiring W <b> 2 is a path for outputting a drive signal (operation target value) corresponding to the first detected voltage value detected by the microcomputer 710 on the wiring W <b> 1 to the drive circuit 764. The wiring W3 is a path for the drive circuit 764 to drive the switching element 12 of the PFC circuit 201 based on the drive signal output from the microcomputer 710. The wiring W4 is a path for the microcomputer 710 to detect a voltage generated in the resistor 35 provided in the LED current path. The wiring W5 is a path for outputting a drive signal (operation target value) corresponding to the second detected voltage value detected by the microcomputer 710 through the wiring W4 to the drive circuit 764. The wiring W6 is a path for the drive circuit 764 to drive the switching element 31 of the buck converter circuit 301 based on the drive signal output from the microcomputer 710. In the sixth modification shown in FIG. 13, the microcomputer 710 and the drive circuit 764 are housed in a single IC package, so that they are scattered in the lighting device as separate IC packages (comparative example in FIG. 14). Compared with the reference), the wirings W1 to W6 can be remarkably shortened.

  The lighting control IC 760 includes various terminals described below, and realizes lighting control by exchanging electrical signals through these terminals. The Vin terminal is connected to the microcomputer 710 and is used for input voltage detection of the lighting SW power supply circuit 251. The PFCZCD terminal is connected to the microcomputer 710, is connected to the secondary winding 11 a of the choke coil 11, and is used for zero cross detection of the current flowing through the PFC circuit 201. The PFCI terminal is connected to the microcomputer 710, is connected to the connection point between the source of the switching element 12 and the resistor 15, and is used for overcurrent detection of the PFC circuit 201. The PFCDR terminal is connected to the drive circuit 764 and outputs a gate signal for driving the switching element 12 of the PFC circuit 201. The PFCV terminal is connected to the microcomputer 710, and is used for feedback control of the PFC circuit 201, overvoltage detection of the PFC circuit, and PFC feedback loop abnormality detection.

  The VB terminal charges the bootstrap capacitor CBS in order to drive the switching element 31 for high side driving. The LEDDR terminal is connected to the drive circuit 764 and outputs a gate signal for driving the switching element 31 of the buck converter circuit 301. The VS terminal is connected to the drive circuit 764 and is a terminal that supplies a reference potential of the switching element 31 that is driven on the high side. The LEDZCD terminal is connected to the microcomputer 710, is connected to the secondary winding 33a of the choke coil 33, and is used to detect zero crossing of the current flowing through the buck converter circuit 301. The LEDI terminal is connected to the microcomputer 710, and is a terminal used for LED current detection and output overcurrent detection for feedback control of the LED current. The LEDV terminal is connected to the microcomputer 710 and is a terminal for detecting output overvoltage and detecting whether or not the light source module 400 is connected.

  The DimIn terminal is connected to a dimmer provided outside the lighting device 151 via a dimming interface circuit. The DimIn terminal receives a dimming signal (PWM signal) from the dimmer, and is a serial communication terminal for UART (Universal Asynchronous Receiver Transmitter) communication. The UART is a circuit that performs mutual conversion between a serial signal and a parallel signal by an asynchronous method, and is formed in the digital chip 762. The GND1 (SIG) terminal is a terminal connected to the ground potential, and is for a small signal ground. The GND2 (PW) terminal is a terminal connected to the ground potential and is for power ground. The DCDCS terminal is connected to the source S of the constant voltage generation circuit unit 511. The DCDCFB1 terminal and the DCDCFB2 terminal are feedback terminals of the control power supply IC unit 510. The Vcc1 terminal is connected to the capacitor 50, and is a terminal to which, for example, 15V is applied as the first control power supply voltage. For example, 5 V is applied to the Vcc2 terminal as the second control power supply voltage. This 5V is used as a power supply voltage for operating the microcomputer 710 on the digital chip 762.

  FIG. 13 shows a detailed circuit configuration of the control power supply circuit 520. The drain D of the constant voltage generation circuit unit 511 is connected to the output side of the PFC circuit 201 via the PFCV terminal. One end of the choke coil L1 as a passive element is connected to the source S of the constant voltage generation circuit unit 511, and the other end of the choke coil L1 is connected to the positive electrode of the capacitor 50. The cathode of the diode D1 is connected to the source S of the constant voltage generation circuit unit 511, and the anode of the diode D1 is connected to the negative electrode of the capacitor 50. A step-down chopper circuit configured by a switching element included in the constant voltage generation circuit unit 511, the diode D1, and the choke coil L1 charges the capacitor 50. Note that the source S of the constant voltage generation circuit unit 511 and a DCDCFB1 terminal described later are connected via a series circuit of resistors R1 and R2. The voltage divided by the resistors R1 and R2 is input from the DCDCFB2 terminal to the feedback terminal FB of the constant voltage generation circuit unit 511. A capacitor C2 is connected in parallel to the series circuit of the resistors R1 and R2. The regulator 522 steps down the voltage (for example, 15V) input to the Vcc1 terminal of the lighting control IC 760 and supplies 5V to the Vcc2 terminal. The voltage at the Vcc1 terminal is transmitted to the DCDCFB1 terminal through the diode D2.

  The lighting control IC 760 further includes protection elements Cfa and Cfb used for electrical protection of the microcomputer 710. The protection elements Cfa and Cfb are formed on the analog chip 761. Specifically, the protection elements Cfa and Cfb are capacitors that function as noise filters. The protective element Cfa is connected in parallel to the voltage dividing resistor in the wiring W1. One end of the protection element Cfb is connected to the wiring W4, and the other end of the protection element Cfb is connected to the ground wiring 770. Thus, the wirings W1 and W4 are voltage detection paths used for output detection of the PFC circuit 201 and the buck converter circuit 301. By providing the protection elements Cfa and Cfb in these voltage detection paths, malfunction due to external noise or the like can be prevented. Further, since the protection elements Cfa and Cfb are housed in the IC package, the number of parts constituting the lighting device 151 can be reduced as compared with the case where these protection elements are externally attached to the lighting control IC 760. Note that protective elements may also be provided for the wirings W2, W3, W5, and W6. Further, the configuration of the protection element is not limited, and an RC filter or an overvoltage element can be used. The overvoltage element is an element that protects the microcomputer 710 from an overvoltage, and may specifically be a clip diode or a Zener diode.

  Here, the relationship between the first embodiment described above and the first and third inventions described in the means for solving the above problems will be described. In the first embodiment described above, the lighting switching power supply circuits 250 and 251 correspond to the “lighting switching power supply circuit” in the first and third inventions, and the control power supply SW power supply circuit 500 is the first power supply circuit. The control power supply IC unit 510 corresponds to “at least part of the control power supply circuit unit” in the first and third inventions, and corresponds to the PFC control circuit 210. The first drive circuit included in the second drive circuit and the second drive circuit included in the buck converter control circuit 310 correspond to the “drive circuit” in the first and third inventions, and the microcomputers 610 and 710 are the first and third inventions described above. This corresponds to the “digital arithmetic circuit” in FIG. In the sixth modification shown in FIG. 13, the drive circuit 764 corresponds to the “drive circuit” in the first and third aspects of the invention. Moreover, the lighting fixture provided by Embodiment 1 and its modification is equivalent to the "lighting device" in 5th invention.

Embodiment 2. FIG.
The lighting device 152 according to the second embodiment does not include the control power SW power circuit 500 but includes a control power generation unit 501 instead. Further, the lighting control IC 700 is replaced with a lighting control IC 780. is there. The lighting device 152 includes a lighting SW power supply circuit 252 that combines the PFC circuit 200 and the buck converter circuit 301. Except for this point, the lighting device 152 according to the second embodiment has the same circuit configuration as the lighting device 150 according to the first embodiment. Therefore, in the following description, the same or corresponding components as those in the first embodiment will be described with the same reference numerals, and differences from the first embodiment will be mainly described, and common items will be briefly described. Or omitted.

  FIG. 15 is a circuit block diagram illustrating a lighting device 152 according to the second embodiment and a lighting fixture including the lighting device 152. The main difference from the first embodiment is that the lighting control IC 780 does not include the control power supply IC unit 510 and includes the activation circuit 80, and the microcomputer 610 executes a control program for generating the control power supply. It is to be. That is, in the first embodiment, the control power IC unit 510 is integrated into the lighting control IC 700, and so to speak, hardware control power generation means is mounted on the lighting control IC 700. On the other hand, since it is possible to generate control power by software control of the microcomputer 610 without providing a hardware circuit for generating control power, the second embodiment generates such software control power. A lighting control IC 780 equipped with means is provided. By integrating software control power generation means into the microcomputer 610 in the analog / digital composite IC package, the number of parts constituting the lighting device 152 can be reduced also in the second embodiment.

  In the lighting device 152 illustrated in FIG. 15, a control power generation unit 501 is connected to the secondary winding 33 a of the choke coil 33. The control power supply generation unit 501 includes an extraction circuit 521 configured with current limiting elements such as a diode 51 and a resistor 52, and capacitors 50 and 70. The anode of the diode 51 is connected to the secondary winding 33 a, and the cathode of the diode 51 is connected to the positive electrodes of the capacitors 50 and 70 via the resistor 52. Since the switching element 31 of the buck converter circuit 301 oscillates, the capacitors 50 and 70 can be charged from the secondary winding 33 a through the diode 51 and the resistor 52. The secondary winding 33 a, the diode 51, and the resistor 52 correspond to “extraction means” that extracts electrical energy output from the lighting SW power supply circuit 252.

  When the microcomputer 610 executes the control program in the above configuration, the control power supply is generated even in the standby mode in which the light source module 400 is turned off. Specifically, the “standby mode” is when the output voltage of the lighting SW power supply circuit 252 is lower than the voltage necessary for lighting the light source module 400 and the lighting control IC 780 is used to relight the light source module 400. This is the mode in which the power is turned on. In the standby mode, when it is necessary to relight, the light source module 400 can be lighted by quickly increasing the voltage by restarting the driving of the lighting SW power supply circuit 252. The microcomputer 610 stores a control program in a built-in memory, and the arithmetic processing unit executes this control program.

  The lighting control IC 780 monitors the voltage (load voltage) applied to the light source module 400 by detecting the resistance divided value by the resistors 39 and 40. When the light source module 400 is turned off and shifts to the standby mode, the microcomputer 610 controls the buck converter circuit 300 while suppressing the output to a voltage that does not light the light source module 400 based on the monitored load voltage. . Thus, the capacitors 50 and 70 are charged by the low output operation of the buck converter circuit 301 so that the capacitor 50 can stably supply a voltage of a magnitude required as a control power supply during the standby mode. In order to realize this operation, the control program performs constant voltage control of the lighting SW power supply circuit 252 so that a predetermined control power supply voltage is applied to the capacitor 50 in the standby mode after the light source module 400 is turned off. It is configured as follows. When the microcomputer 610 executes the control program, the output voltage of the lighting SW power supply circuit 252 is controlled to a constant target voltage value. This target voltage value is less than the voltage at which the light source module 400 is lit in the standby mode, and is equal to or higher than the control power supply voltage (for example, 15 V) of the PFC control circuit 210 and the back converter control circuit 310. Since the control power supply voltages of the PFC control circuit 210 and the buck converter control circuit 310 are higher than the control power supply voltage of the microcomputer 610, the power supply of the microcomputer 610 can be secured if the target voltage value is in the above range. The capacitors 50 and 70 are provided outside the lighting control IC 780 and are charged with the electric energy output from the buck converter circuit 301. Thereby, the control power supply voltage can be obtained from the control power supply generation unit 501. The position where the capacitor 50 is provided is not particularly limited to the inside or outside of the lighting control IC 780, and may be provided inside the lighting control IC 780.

  The activation circuit 80 is a circuit for activating the lighting control IC 780 when the lighting device 152 is activated from the complete stop state. In a state where the lighting device 152 is completely stopped, the capacitors 50 and 70 have no electric charge, and a control power source cannot be obtained. Therefore, the starting circuit 80 obtains a starting current from the positive electrode side of the capacitor 14, thereby generating a power source at the time of starting.

  FIG. 16 is a diagram illustrating a schematic configuration of the lighting device 152 according to the second embodiment. FIG. 17 is a diagram illustrating a schematic configuration of the lighting control IC 780 according to the second embodiment. This is different from the first embodiment (see FIGS. 2 and 3) in that the control power supply IC unit 510 is not provided. As shown in FIG. 17, the lighting control IC 780 includes ground terminals 731 and 733, internal ground wirings 720 and 721, external ground wiring 720c, control power supply terminals 732 and 734, internal power supply wirings 722 and 723, and external power supply wiring 735. Is provided. Also in the second embodiment, various “ground or / and control power supply wiring sharing technologies” described in the first embodiment and the first to fifth modifications thereof can be applied. This is because the circuit connection relationship described with reference to FIGS. 2 to 12 may be applied after removing the control power supply IC unit 510. Therefore, further explanation is omitted in this point in order to avoid redundant explanation.

  FIG. 18 is a circuit block diagram illustrating a lighting device 153 and a lighting fixture including the lighting device 153 according to the first modification of the second embodiment. In the modification shown in FIG. 18, the control power generation unit 501 is replaced with a control power generation unit 502. The lighting SW power supply circuit 250 includes a buck converter circuit 300 that does not include the secondary winding 33a, and is the same as that in the first embodiment. In the control power generation unit 502, a snubber circuit 502 a is connected to a connection point between the switching element 31 and the inductor 33. The snubber circuit 502 a is composed of a capacitor 53, a diode 54, and a resistor 52, and takes out power from the buck converter circuit 300. The snubber circuit 502 a corresponds to “extraction means” that extracts the electrical energy output from the lighting SW power supply circuit 250.

  FIG. 19 is a circuit block diagram illustrating a lighting device 154 and a lighting fixture including the lighting device 154 according to the second modification of the second embodiment. The modification shown in FIG. 19 corresponds to a modification in which the lighting device 152 according to the second embodiment is changed to a full digital power supply. This second modified example is similar to the lighting device 151 (see FIG. 13) according to the sixth modified example in which the lighting device 150 according to the first embodiment is a full digital power source. About the structure which attached | subjected the same code | symbol in FIG. 19 and FIG. 13, description is simplified thru | or abbreviate | omitted as what is provided with the same structure and function. In the lighting control IC 790 shown in FIG. 19, the control power supply IC unit 510 is not provided in the analog chip 761, and a startup circuit 80 is provided instead.

  Here, the relationship between the second embodiment described above and the second and fourth inventions in the means for solving the above-described problems will be described. In the second embodiment described above, the lighting switching power supply circuits 250 to 252 correspond to the “lighting switching power supply circuits” in the second and fourth inventions, and the capacitors 50 and 70 are the second and fourth capacitors. The first drive circuit included in the PFC control circuit 210 and the second drive circuit included in the buck converter control circuit 310 correspond to the “drive circuit” in the second and fourth inventions. Reference numerals 610 and 710 correspond to the “digital arithmetic circuit” in the second and fourth aspects of the invention. In the modification shown in FIG. 19, the drive circuit 764 corresponds to the “drive circuit” in the second and fourth inventions. Moreover, the lighting fixture provided by Embodiment 2 and its modification is equivalent to the "lighting device" in 5th invention.

Embodiment 3 FIG.
FIG. 20 is a circuit block diagram illustrating a lighting device 155 and a lighting fixture including the lighting device 155 according to the third embodiment. The lighting device 155 according to the third embodiment is similar to the lighting device 151 according to the sixth modified example (see FIG. 13) of the first embodiment in that it is a full digital power supply device. In the following description, the same or corresponding components as those in the sixth modification of the first embodiment will be described with the same reference numerals, and differences from the sixth modification of the first embodiment will be mainly described. However, explanations of common matters are simplified or omitted.

  The lighting device 155 includes a circuit similar to the lighting device 151 except that the lighting control IC 760 is replaced with a lighting control IC 800 and an external interface 620 and a power supply line 806 are added.

  The lighting control IC 800 includes a microcomputer 710 in which a DimIn2 terminal to a RESET terminal and a protection circuit 804 are added to the lighting control IC 800, and a digital communication function is further improved. The DimIn2 terminal is used to forcibly select a table stored in a built-in memory (not shown) of the microcomputer 710, and is a serial communication terminal of the UART communication system. The DATUPDW terminal is a terminal for adjusting the operation of the circuit. The ProW terminal is a terminal used for writing internal data in a nonvolatile memory (for example, a flash memory, not shown) built in the microcomputer 710. Thereby, the program of the microcomputer 710 can be rewritten. When a predetermined signal is input to the RESET terminal, the microcomputer 710 that has received the predetermined signal is reset. The lighting control IC 800 includes a Vin terminal to a Vcc2 terminal similarly to the lighting control IC 800. Since the details of these terminals are as described in the sixth modification of the first embodiment, description thereof is omitted here. The protection circuit 804 is built in the analog chip 802.

  The microcomputer 710 communicates a digital signal with the additional unit 621 provided outside the lighting control IC 800 via the digital communication terminal F1. The digital communication terminal F1 includes a DimIn terminal to a RESET terminal. The digital chip 762 includes a serial communication circuit (specifically, UART) for performing serial communication via the digital communication terminal F1. Signals are exchanged with the outside of the lighting control IC 800 by serial communication via the digital communication terminal F1. Except for this point, it has the same configuration and function as the microcomputer 710 according to the sixth modification of the first embodiment. The microcomputer 710 may be replaced with another digital arithmetic circuit such as a DSP as in the sixth modification of the first embodiment.

  The external interface 620 is a terminal for digital communication provided outside the IC package. The digital communication line 805 connects the digital communication terminal F1 and the external interface 620. One end of the power supply line 806 is connected to a connection point where the Vcc1 terminal, the control power supply circuit 520, and the capacitor 50 are connected to each other. The other end of the power supply line 806 is connected to the external interface 620, and the control power is supplied to the external interface 620. Thereby, power can be supplied to the additional unit 621 connected to the digital communication terminal F <b> 1 through the feeder line 806. As the external interface 620, for example, a USB (Universal Serial Bus) connector may be applied.

  Some of the terminals constituting the digital communication terminal F1 are functionally classified into a digital signal communication terminal F1a and an access terminal F1b. The digital signal communication terminal F1a includes a DimIn terminal and a DimIn2 terminal. Electronic data related to control of the light source module 400 is transmitted to the microcomputer 710 via the digital signal communication terminal F1a. The access terminal F1b includes a ProW terminal used for rewriting the program of the microcomputer 710 and a RESET terminal used for resetting the microcomputer 710. At least one of erasing, writing, and reading of electronic data is performed on the memory of the microcomputer 710 via the access terminal F1b.

  The lighting control IC 800 further includes communication lines W7 to W11 and a protection circuit 804 connected to the communication lines W7 to W11. The communication lines W7 to W11 connect the digital communication terminal F1 and the microcomputer 710 inside the IC package. The protection circuit 804 includes protection elements Cf1 to Cf5 for electrical protection connected to the communication lines W7 to W11 inside the IC package. Specifically, the protection elements Cf1 to Cf5 in the third embodiment are capacitors that function as noise filters, similarly to the protection elements Cfa and Cfb. The protection elements Cf1 to Cf5 can be variously modified, and a filter or the like for preventing malfunction due to overvoltage of the digital communication terminal F1 or external noise is applied. The protection circuit 804 is formed on the analog chip 802. Thereby, compared with the case where a protection element is connected to lighting control IC800 outside, the number of parts which constitute lighting device 155 can be reduced. The protection element assumed as a variation may be an overvoltage protection element, specifically a clamp diode or a Zener diode, and further includes a noise filter such as an RC filter.

  Since the above-described configuration such as the analog chip 802 including the protection circuit 804 and the digital communication terminal F1 is provided in the lighting control IC 800, a desired function and high-quality communication can be achieved only by combining the lighting control IC 800 with a small number of peripheral components. Possible digital communication functions can be obtained. Thereby, compared with the case where the lighting control IC 800 and the protection elements Cf1 to Cf5 are separately mounted as components of the lighting device 155, the number of components can be drastically reduced. Thereby, digital communication can be performed with the additional unit 621 provided outside the lighting control IC 800 while reducing the number of components.

  FIG. 21 is a perspective view of a lighting fixture 850 according to the third embodiment. A lighting device 155 and a light source module 400 are provided in a housing 851 of the lighting fixture 850. As an example, the additional unit 621 includes an electrode connected to the external interface 620 of the lighting device 155, a sensor unit that performs a command from the user or determination of an external state, and the signal detected by the sensor unit as a control signal for command. A control circuit is provided for converting and transmitting this control signal to the lighting device 155 via an external interface 620 connected to the electrode and wiring. Since the additional unit 621 is electrically connected to the digital communication terminal F1 of the lighting control IC 800 via the external interface 620, digital communication can be performed between the additional unit 621 and the microcomputer 710.

  The additional unit 621 changes the specifications of the sensor unit and the control circuit, for example, a wireless communication unit, an infrared remote control unit, a human sensor unit, an illuminance sensor unit, a draw string unit, a step dimming unit, a PLC (Power Line Communication). ) Unit, connector unit and the like. Thereby, various added values can be attached to the lighting device 155.

  A case where the additional unit 621 is a “wireless communication unit” will be described. The wireless communication unit includes a wireless communication antenna that transmits and receives signals from the outside, and a wireless communication control circuit that converts signals transmitted and received from the wireless communication antenna and transmits and receives command signals to and from the lighting control IC 800. For example, an external lighting control device (not shown) such as a remote controller or a dimming controller provided with wireless communication means transmits a command signal that matches the application, such as changing the brightness of the light source module 400. The radio communication antenna receives the signal, and the radio communication control circuit converts the received signal into a control signal. This control signal is finally transmitted to the microcomputer 710 of the lighting control IC 800 via the digital communication terminal F1.

  A plurality of additional units 621 having the same shape and different functions may be lined up and exchanged. The user can select a function and specification and attach a desired additional unit to the lighting device 155 in a replaceable manner. By exchanging the additional unit 621, different functions can be added to the lighting device, and the specifications of the lighting device can be changed with a high degree of freedom.

  FIG. 22 is a circuit block diagram of another lighting fixture 860 according to the third embodiment. The lighting fixture 860 includes the additional unit 621 as a “control module” and the wireless communication module 622 as a component. The lighting fixture 860 includes a light source module 400, a lighting device 155, a wireless communication module 622, and an additional unit 621. The wireless communication module 622 wirelessly communicates with other lighting fixtures (not shown). The additional unit 621 receives a user or external state command and transmits the command to the lighting device 155 and the wireless communication module 622.

  When the additional unit 621 receives a user or external state command, the command is transmitted to the lighting device 155, and the lighting device 155 controls the light source module 400 to be turned on. Further, the additional unit 621 transmits the same command to the wireless communication module 622 at the same time as transmitting the command to the lighting device 155. The wireless communication module 622 that has received the command transmits the command from the additional unit 621 to another lighting fixture. That is, the lighting fixture 860 becomes the master, and the lighting control of the light source modules of the other lighting fixtures is performed similarly to the light source module 400 of the lighting fixture 860.

  An external interface 620 included in the lighting device 155 is connected to the additional unit 621. The external interface 620 includes a Vcc terminal that supplies power, an Rx terminal that receives a command, a Tx terminal that returns a response to the command, and a circuit GND terminal. The Vcc terminal is connected to the power supply line 806 in the lighting control IC 800. The Rx terminal is connected to the DimIn terminal, and the Tx terminal is connected to the DimIn2 terminal. The GND terminal may be connected to the GND1 (SIG) terminal in the lighting control IC 800.

  The wireless communication module 622 includes, as terminals 622a connected to the additional unit 621, a Vcc terminal to which power is supplied, a Tx terminal that transmits a command or answer, an Rx terminal that receives a command or answer, and a circuit GND terminal. Have

  The additional unit 621 includes a first terminal 621 a connected to the external interface 620 and a second terminal 621 b connected to the wireless communication module 622. The first and second terminals 621a and 621b are independent serial ports. The first and second terminals 621a and 621b each have a Vcc terminal to which power is supplied, a Tx terminal that transmits a command, an Rx terminal that receives an answer, and a circuit GND terminal. The additional unit 621 may communicate with the lighting device 155 and the wireless communication module 622 with the same command of the common protocol.

  The external interface 620 and the second terminal 621b of the additional unit 621 may be configured with the same interface. The first terminal 621a of the additional unit 621 and the terminal 622a of the wireless communication module 622 may be configured with the same interface. Accordingly, the terminal 622a of the wireless communication module 622 can be inserted into the external interface 620 in the same manner as the terminal 622a of the additional unit 621 is inserted. Therefore, it is also possible to communicate by directly connecting the wireless communication module 622 and the lighting device 155.

  The communication protocol may be a 4-byte configuration of STX (start command), CM (command), and two FDs (frame data). STX (start command) is a command that is a signal for transmitting a command, and transmits a fixed command. When this command is received, the remaining 3 bytes of the command are followed. CM (command) is a command indicating the content of the command. For example, the command indicates a lighting ON / OFF operation of the light source module 400 or a dimming rate operation command for changing the brightness. The FD (frame data) is a command indicating the specific contents of the command, and indicates a specific command or numerical value such as lighting ON of the light source module 400 or dimming rate of 50%, for example.

  The additional unit 621 includes a power supply circuit 627. The power supply circuit 627 supplies power supplied from the lighting device 155 via the first terminal 621a to the control circuit 621d and the second terminal 621b. The control circuit 621d performs bidirectional serial communication via the first and second terminals 621a and 621b. The command circuit 626 receives the command of the user or the external state, and transmits the command to the lighting device 155 and the wireless communication module 622 via the control circuit 621d. The additional unit 621 has an independent serial port, but communicates with the lighting device 155 and the wireless communication module 622 with the same command of the common protocol. The control circuit 621d is realized by a processing circuit such as a CPU or a system LSI that executes a program stored in a memory. In addition, a plurality of processing circuits may cooperate to execute the above function.

  As described above, when the command circuit 626 of the additional unit 621 receives the command of the user or the external state and transmits the command to the lighting device 155, the lighting device 155 controls the light source module 400 to turn on according to the command. be able to. Further, the additional unit 621 communicates with the lighting device 155 and the wireless communication module 622 with the same command of the common protocol, so that the wireless communication module 622 communicates wirelessly with other lighting fixtures and uses the light source modules of the other lighting fixtures. The lighting control can be performed similarly to the light source module 400 of 860.

  Command circuit 626 may be formed of a “human sensor”. When the presence sensor detects the presence of a person, the presence sensor transmits a presence determination signal to the control circuit 621d. When the presence sensor does not detect the presence of a person, the presence sensor transmits a presence determination signal to the control circuit 621d. The control circuit 621d transmits a presence determination signal or an absence determination signal to the lighting device 155 and the wireless communication module 622 with the same command using a common communication protocol. Thereby, lighting control of the light source module 400 can be performed according to the presence or absence of a person, and the lighting control can be performed by wireless communication with other lighting fixtures. It should be noted that the human sensor determines that the person is absent if the presence of the person is not detected for a predetermined time after the presence of the person is detected.

  The command circuit 626 may be an “illuminance sensor”. The illuminance sensor detects the brightness of the external state and transmits a signal to the control circuit 621d. The control circuit 621d transmits a signal corresponding to the brightness to the lighting device 155 and the wireless communication module 622 with the same command using a common communication protocol. Thereby, it is possible to control the lighting of the light source module 400 according to the brightness of the external environment, and to control the lighting by wirelessly communicating with other lighting fixtures.

  The command circuit 626 may be composed of a “light receiving element”. The user transmits the set values of the brightness, lighting time, and extinguishing time of the lighting fixture 860 with a remote controller (not shown). The light receiving element receives this signal and transmits the signal to the control circuit 621d. The control circuit 621d transmits a signal to the lighting device 155 and the wireless communication module 622 with the same command using a common communication protocol. Thereby, it is possible to control the lighting of the light source module 400 in accordance with a user's command and to perform lighting control by wireless communication with other lighting fixtures.

  The command circuit 626 may be configured by a “switch” through which a user inputs a command. When the user operates the switch, a stepwise signal is transmitted to the control circuit 621d. Thereby, it is possible to control the lighting of the light source module 400 in accordance with a user's command and to perform lighting control by wireless communication with other lighting fixtures. The stepwise signal of the switch is used, for example, at the time of step dimming that changes the brightness stepwise, and the lighting device 155 receives this signal and changes the brightness of the light source module 400 stepwise.

  A lighting system including at least two or more lighting fixtures in which the lighting fixture 860 is a master and another lighting fixture wirelessly communicating with the master lighting fixture may be constructed. Similar to the lighting fixture 860, the slave lighting fixture includes the light source module 400, the wireless communication module 622, and the lighting device 155. In this lighting system, since the master lighting fixture 860 is provided, it is not necessary to attach a lighting control device. Moreover, since the lighting fixture 860 and the plurality of slave lighting fixtures perform wireless communication with each other, no wiring work is required.

  Note that the features of the first and second embodiments and the features of the third embodiment can be combined. That is, in the third embodiment, the first and second embodiments and the modifications thereof can be applied. In other words, the digital communication terminal F1, the communication line 805, the protection circuit 804, the power supply line 806, the external interface 620, and the additional unit 621 in the third embodiment are different from those in the first and second embodiments and their modifications. May be applied. Further, in the lighting control IC 800 in the third embodiment, as in the first embodiment, the control power supply IC unit 510 is housed in the IC package. However, in the third embodiment, the control power supply IC unit 510 may be provided outside the lighting control IC 800, and in this case as well, technical effects relating to the digital communication terminal F1 and the protection circuit 804 described in the third embodiment are included. Can be obtained.

150 to 155 Lighting device, 11, 33 Choke coil, 11a, 33a Secondary winding, 12, 31 Switching element, 80 Start-up circuit, 100 Input filter rectifier, 110 Input filter circuit, 200, 201 Power factor improvement circuit (PFC) Circuit), 210 PFC control circuit, 250, 251, 252 lighting switching power supply circuit (lighting SW power supply circuit), 300, 301 buck converter circuit, 310 buck converter control circuit, 400 light source module, 500 switching power supply circuit for control power supply (SW power supply circuit for control power supply), 501 and 502 Control power generation unit, 502a Snubber circuit, 510 Control power supply IC unit, 520 Control power supply circuit, 521 Extraction circuit, 522 Regulator, 610, 710 Microcomputer (microcomputer), 620 External interface, 621 additional unit, 621a first terminal, 621b second terminal, 621d control circuit, 622 wireless communication module, 622a terminal, 626 command circuit, 627 power supply circuit, 701, 761, 802 analog chip, 702, 762 Digital chip, 720, 721, 724, 727, 728, 729a, 729b, 770 Internal ground wiring, 720c External ground wiring, 722, 722a, 723, 726 Internal power supply wiring, 727a, 727b, 728a, 728b Branch wiring section, 731 733, ground terminal, 732, 734 control power supply terminal, 735 external power supply wiring, 764 drive circuit, 766 constant current circuit, 804 protection circuit, 805 digital communication line, 806 power supply line, 850, 860 851 housing, 860 lighting fixture, 900 printed circuit board, CBS bootstrap capacitor, Cf1-Cf5, Cfa, Cfb protection element, F1 digital communication terminal, F1a digital signal communication terminal, F1b access terminal, G1-G4, Gp, Gb , Gc, Gv, Gm ground, 700 to 800 lighting control IC, W1 to W6 wiring, W7 to W11 communication line

Claims (13)

A switching power supply for lighting that generates a DC power supply using a switching element and lights a light source with the DC power supply;
A lighting control IC for controlling the switching power supply circuit for lighting;
With
The lighting control IC is
A digital chip portion provided with a digital arithmetic circuit for performing an operation for controlling the switching power supply circuit for lighting;
An analog chip unit provided with a drive circuit for driving the switching element, and at least part of a control power supply circuit unit for generating a control power supply for the digital arithmetic circuit and the drive circuit;
Is a lighting device that is housed in a single package. The lighting control IC is
A ground terminal having one end exposed to the outside of the package;
An internal ground wiring connected to the other end of the ground terminal, the analog chip portion, and the digital chip portion in the package;
With
The internal ground wiring includes a junction wiring portion connected to the other end of the ground terminal, and a plurality of branch wiring portions branched from the junction wiring portion,
A first circuit of the at least part of the control power supply circuit unit, the digital arithmetic circuit, and the drive circuit is connected to a first branch wiring unit of the plurality of branch wiring units,
2. The second circuit of claim 1, wherein a second circuit of the at least part of the control power circuit unit, the digital arithmetic circuit, and the drive circuit is connected to a second branch wiring unit of the plurality of branch wiring units. Lighting device. The first circuit includes the at least part of the control power supply circuit unit and the drive circuit,
The lighting device according to claim 2, wherein the second circuit includes the digital arithmetic circuit. The first circuit includes the drive circuit;
The lighting device according to claim 2, wherein the second circuit includes the at least part of the control power supply circuit unit and the digital arithmetic circuit. The switching power supply circuit for lighting is
A power factor correction circuit;
A buck converter circuit for stepping down a DC voltage supplied from the power factor correction circuit;
Including
The drive circuit includes a first drive circuit that drives the switching element of the power factor correction circuit, and a second drive circuit that drives the switching element of the buck converter circuit,
The lighting device according to claim 4, wherein both the first and second drive circuits are connected to the first branch wiring portion. The lighting control IC is
A first ground terminal having one end exposed outside the package;
A second ground terminal having one end exposed outside the package;
Inside the package, a first internal ground wiring that connects the first circuit and the other end of the first ground terminal among the at least part of the control power supply circuit unit, the digital arithmetic circuit, and the drive circuit. When,
Inside the package, a second internal ground wiring that connects the second circuit and the other end of the second ground terminal among the at least part of the control power supply circuit unit, the digital arithmetic circuit, and the drive circuit. When,
With
The lighting device according to claim 1, further comprising an external ground wiring connected to the first ground terminal and the second ground terminal outside the package. The first circuit includes the at least part of the control power supply circuit unit and the drive circuit,
The lighting device according to claim 6, wherein the second circuit includes the digital arithmetic circuit. The first circuit includes the drive circuit;
The lighting device according to claim 6, wherein the second circuit includes the at least part of the control power supply circuit unit and the digital arithmetic circuit. The analog chip part is provided with an active element constituting the control power circuit part,
A passive element provided outside the package and constituting the control power supply circuit unit together with the active element;
A capacitor provided outside the package, charged in the control power supply circuit unit, and stored charge is used as the control power supply;
The lighting device according to any one of claims 1 to 8, further comprising: A switching power supply for lighting that generates a DC power supply using a switching element and lights a light source with the DC power supply;
A lighting control IC for controlling the switching power supply circuit for lighting;
A capacitor that is provided inside or outside the lighting control IC, is charged with electrical energy output from the lighting switching power supply circuit, and the stored charge is used as a control power source that is a power source of the lighting control IC;
With
The lighting control IC is
A digital chip portion provided with a digital arithmetic circuit for performing an operation for controlling the switching power supply circuit for lighting;
An analog chip portion provided with a drive circuit for driving the switching element;
In one package,
The digital arithmetic circuit performs a calculation process for performing a constant voltage control on the switching power supply circuit for lighting so that a predetermined control power supply voltage is applied to the capacitor in a standby mode after the light source is turned off. .   An illuminating device provided with the lighting device of any one of Claims 1-10. In a lighting control IC that generates a DC power source using a switching element and controls a lighting switching power source circuit that lights a light source with the DC power source,
The lighting control IC is
A digital chip portion provided with a digital arithmetic circuit for performing an operation for controlling the switching power supply circuit for lighting;
An analog chip unit provided with a drive circuit for driving the switching element, and at least part of a control power supply circuit unit for generating a control power supply for the digital arithmetic circuit and the drive circuit;
Is a lighting control IC that is housed in a single package. In a lighting control IC that generates a DC power source using a switching element and controls a lighting switching power source circuit that lights a light source with the DC power source,
The lighting control IC is
A digital chip portion provided with a digital arithmetic circuit for performing an operation for controlling the switching power supply circuit for lighting;
An analog chip portion provided with a drive circuit for driving the switching element;
In one package,
The digital arithmetic circuit is less than the voltage at which the light source is turned on in the standby mode after the light source is turned off, and is equal to or higher than the higher one of the power voltage of the digital arithmetic circuit and the power voltage of the drive circuit. As described above, a lighting control IC that executes arithmetic processing for controlling the output voltage value of the lighting switching power supply circuit at a constant voltage.

Images