JP5783838B2 - Luminescent body driving device and lighting apparatus using the same - Google Patents

Description

  The present invention relates to a light emitter driving apparatus that drives a light emitter such as an LED [light emitting diode], and an illumination device using the same.

  In recent years, various LED driver ICs corresponding to a triac (bidirectional thyristor) dimming method have been put into practical use. The triac dimming method is a dimming method that has been conventionally employed as a dimming method for incandescent bulbs and the like. Therefore, if the LED driver IC corresponding to the TRIAC dimming method is used, the dimming control of the LED lighting device can be performed using the existing triac dimmer.

  As an example of the related art related to the above, Patent Document 1 can be cited.

JP 2010-73689 A

  By the way, the triac dimmer has a structure that causes a malfunction unless a holding current of a predetermined value or more is passed. For this reason, LED lighting devices compatible with the triac dimming method (for example, incandescent light bulb type LED lamps that can replace incandescent light bulbs) include an LED driver IC compatible with the triac dimming method and a triac dimming device that is externally attached to the LED driver IC. A power supply module equipped with a bleeder circuit for maintaining the holding current of the optical device has been incorporated.

  The bleeder circuit is effective as a means for preventing malfunction of the triac dimmer. However, when an LED lighting device equipped with a bleeder circuit is used as a light source of an illumination system that does not include a triac dimmer, the current flowing through the bleeder circuit becomes a meaningless loss. Therefore, there are two types of conventional LED lighting devices: a dimmable model that supports the TRIAC dimming method (model equipped with a bleeder circuit) and a non-dimmed model (model that does not incorporate a bleeder circuit). This resulted in increased manufacturing costs and user confusion.

  The present invention has been made in view of the above-described problems found by the inventors of the present application, and an object of the present invention is to provide a light emitter driving device capable of reducing loss generated in a bleeder circuit, and an illumination device using the same. And

  In order to achieve the above object, a light emitter driving device according to the present invention includes a dimmer presence / absence determining unit that compares the phase angle of a rectified voltage with a predetermined reference phase angle to determine the presence or absence of a dimmer, A bleeder control unit that performs enable control of the bleeder circuit in accordance with the determination result of the dimmer presence / absence determination unit (first configuration).

  In the light emitter driving device having the first configuration, the dimmer presence / absence determining unit determines that there is a dimmer when the phase angle of the rectified voltage is smaller than the reference phase angle, and the rectifier A configuration (second configuration) for determining that there is no dimmer when the phase angle of the voltage is larger than the reference phase angle may be used.

  Further, in the light emitter driving device having the second configuration, the bleeder control unit enables the bleeder circuit according to the determination result with the dimmer, and according to the determination result without the dimmer. The bleeder circuit may be disabled (third configuration).

  Further, in the light emitter driving device having the third configuration, when the bleeder control unit enables the bleeder circuit in accordance with a determination result that there is a dimmer, the rectified voltage falls below a threshold voltage. The bleeder circuit is controlled so that a bypass current from the application terminal of the rectified voltage to the ground terminal flows in a period of time, and the current flowing through the dimmer is although the rectified voltage exceeds the threshold voltage. The bleeder circuit is controlled to flow a bleeder current to the dimmer during a period of time below the threshold current, the rectified voltage is higher than the threshold voltage, and the current flowing through the dimmer is The bleeder circuit is controlled to stop the bypass current and the bleeder current in a period exceeding the threshold current, while no dimmer is used. When the bleeder circuit and disabled in response to the constant result is always better to structure for controlling the bleeder circuit to stop the bypass current and the bleeder current (fourth configuration).

  Further, in the light emitter driving device having any one of the first to fourth configurations, the dimmer presence / absence determining unit maintains the determination result with the dimmer while determining without the dimmer. About the result, it is good to set it as the structure (5th structure) which repeats the presence / absence determination of the said light controller regularly, without maintaining this.

  The light emitter driving device having any one of the first to fifth configurations includes a comparator that compares the rectified voltage with the threshold voltage to generate a comparison signal, and a high level period and a low level of the comparison signal. A configuration further comprising: a sampling counter that measures a period; a phase angle calculation unit that calculates a phase angle of the rectified voltage based on an output of the sampling counter; and a reference phase angle storage unit that stores the reference phase angle. A sixth configuration) may be used.

  The lighting device according to the present invention includes a light emitter, a rectifier circuit that rectifies an alternating voltage to generate the rectified voltage, a smoothing circuit that generates a direct current voltage from the rectified voltage and supplies the rectifier to the light emitter, A bleeder circuit that maintains the holding current of the triac dimmer, a switch element that conducts / cuts off a current path through which the driving current of the light emitter flows, and on / off control of the switch element according to the phase angle of the rectified voltage It is good to make it the structure (7th structure) which has a light-emitting-body drive device which consists of any one of the said 1st-6th structure which performs.

  In the illumination device having the seventh configuration, the light emitter may have a configuration including an LED element (eighth configuration).

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the light-emitting body drive device which can reduce the loss which arises in a bleeder circuit, and an illuminating device using the same.

The figure which shows one structural example of LED lighting equipment The figure which shows the example of 1 structure of the decoder part 110, the bleeder control part 140, and the bleeder circuit BLD. The figure which shows the operation example of the comparator 111 and the sampling counter 112 The figure which shows the example of 1 setting of reference | standard phase angle S2 Flow chart showing an example of dimmer presence / absence determination operation The figure which shows the 1st switching example (with dimmer) of bleeder control mode The figure which shows the 2nd switching example (the dimmer is not provided) of bleeder control mode

<LED lighting equipment>
FIG. 1 is a diagram illustrating a configuration example of an LED lighting device. The LED lighting device 1 of this configuration example includes an LED module 10 and a power supply module 20.

  The LED module 10 is a light source of the LED lighting device 1 that emits light of daylight color (color temperature of about 5000K) or light bulb color (color temperature of about 3000K), and includes a plurality of LED elements connected in series or in parallel.

  The power supply module 20 converts the AC voltage VIN supplied from a commercial AC power supply 30 (for example, AC 90 to 220 V) into a DC voltage VOUT (for example, DC 50 V) and supplies the converted voltage to the LED module 10. The power supply module 20 includes an LED driver IC 100 and various discrete components (diode bridge DB, bleeder circuit BLD, resistors R1 to R5, diodes D1 to D4, Zener diode ZD, capacitors C1 to C3, npn type externally attached thereto. A bipolar transistor Q1, an N-channel MOS field effect transistor N1, and a transformer TR) are mounted on a printed wiring board.

  The first output terminal of the commercial AC power supply 30 is connected to the first input terminal of the diode bridge DB. The second output terminal of the commercial AC power supply 30 is connected to the second input terminal of the diode bridge DB via a triac dimmer 40 that controls the phase of the AC voltage VIN. The first output terminal of the diode bridge DB is connected to the anode of the diode D1, and is also connected to the ground terminal via the bleeder circuit BLD. The cathode of the diode D <b> 1 is connected to the anode of the LED module 10. The second output terminal of the diode bridge DB is connected to the ground terminal via the bleeder circuit BLD. The control end of the bleeder circuit BLD is connected to the external terminal T2 of the LED driver IC 100.

  The resistors R1 and R2 are connected in series between the first output terminal of the diode bridge DB and the ground terminal. A connection node (applied end of the rectified voltage Va) of the resistors R1 and R2 is connected to the external terminal T1 of the LED driver IC100. The capacitor C1 is connected between the cathode of the diode D1 and the ground terminal. A first terminal of the resistor R3 is connected to the cathode of the diode D1. The second end of the resistor R3 is connected to the cathode of the Zener diode ZD and the base of the transistor Q1. The anode of the Zener diode ZD is connected to the ground terminal. The collector of the transistor Q1 is connected to the cathode of the diode D1 through the resistor R4. The emitter of the transistor Q1 is connected to the external terminal T3 of the LED driver IC 100 and the cathode of the diode D2. The anode of the diode D2 is connected to the ground terminal.

  The cathode of the diode D3 is connected to the cathode of the diode D1. The anode of the diode D3 is connected to the drain of the transistor N1. The source of the transistor N1 is connected to the ground terminal via the resistor R5, and is also connected to the external terminal T5 of the LED driver IC100. The gate of the transistor N1 is connected to the external terminal T4 of the LED driver IC 100. A first end of the capacitor C <b> 2 is connected to the anode of the LED module 10. A second end of the capacitor C <b> 2 is connected to the cathode of the LED module 10.

  A first end of the primary winding L1 forming the transformer TR is connected to the cathode of the LED module 10. The second end of the primary winding L1 is connected to the drain of the transistor N1. The first end of the secondary winding L2 forming the transformer TR is connected to the anode of the diode D4. The second end of the secondary winding L2 is connected to the ground end. The cathode of the diode D4 is connected to the external terminal T3 of the LED driver IC100. The capacitor C3 is connected between the cathode of the diode D4 and the ground terminal.

<Power supply module>
The basic operation of the power supply module 20 having the above configuration will be described in detail.

  The diode bridge DB is a rectifier circuit that generates a rectified voltage Va by full-wave rectifying the AC voltage VIN. The diode D <b> 1 and the capacitor C <b> 1 are a smoothing circuit that smoothes the output of the diode bridge DB to generate a DC voltage VOUT and supplies this to the LED module 10. As described above, the diode bridge DB, the diode D1, and the capacitor C1 function as an AC / DC converter that converts the alternating voltage VIN into the direct voltage VOUT and supplies the converted voltage to the LED module 10. A filter circuit for removing noise and surge may be provided in front of the diode bridge DB.

  The transistor N1 is a switch element that conducts / cuts off a current path from the cathode of the LED module 10 to the ground terminal. The LED driver IC 100 is a semiconductor integrated circuit device that performs on / off control of the transistor N1 so that the current flowing through the ground terminal via the transistor N1 and the resistor R5 (the driving current ILED of the LED module 10) matches the target value. . When the transistor N1 is on, the drive current ILED flows from the cathode of the diode D1 to the ground terminal via the LED module 10, the primary winding L1 of the transformer TR, the transistor N1, and the resistor R5. On the other hand, when the transistor N1 is turned off, the drive current ILED flows in a loop through the primary winding L1, the diode D3, and the LED module 10 of the transformer TR.

  The transistor Q1, the resistors R3 and R4, the diode D2, and the Zener diode ZD draw the charging current of the capacitor C3 from the cathode of the diode D1 when the LED driver IC 100 starts up, and generate the power supply voltage Vb of the LED driver IC 100. Functions as a simple regulator (emitter follower). The transformer TR supplies power to the LED driver IC 100 using the drive current ILED that flows through the LED module 10. Therefore, after the LED driver IC 100 is activated, the capacitor C3 is charged through the current path from the secondary winding L2 of the transformer TR via the diode D4, and the power supply to the LED driver IC 100 is continued. Note that the winding ratio of the transformer TR may be appropriately set in view of the power supply voltage Vb necessary for the operation of the LED driver IC 100.

<LED driver IC>
Next, the internal configuration of the LED driver IC 100 will be described. In the LED driver IC 100, a decoder unit 110, a voltage drop protection unit 120, a regulator unit 130, a bleeder control unit 140, a drive current control unit 150, and a driver unit 160 are integrated. The LED driver IC 100 is integrated with other circuit blocks (temperature protection unit, overvoltage protection unit, overcurrent protection unit, LED short protection unit, LED open protection unit, sky / ground fault protection unit, etc.). It is also possible.

  The decoder unit 110 monitors the rectified voltage Va ′ (divided voltage of the rectified voltage Va) applied to the external terminal T1 from the connection node of the resistors R1 and R2, and generates a dimming signal and a bleeder control signal. According to the LED driver IC 100 including the decoder unit 110, it is possible to perform dimming control of the LED lighting device 1 using the triac dimmer 40 that performs phase control of the AC voltage VIN.

  The voltage drop protection unit 120 monitors whether the power supply voltage Vb applied to the external terminal T3 is lower than a predetermined threshold voltage and generates a voltage drop protection signal.

  The regulator unit 130 generates a predetermined internal power supply voltage from the power supply voltage Vb applied to the external terminal T3 and supplies it to each unit of the LED driver IC 100.

  The bleeder control unit 140 performs drive control of the bleeder circuit BLD based on the bleeder control signal input from the decoder unit 110. With such a configuration, when the holding current of the TRIAC dimmer 40 is insufficient, the normal operation of the TRIAC dimmer 40 can be maintained by causing the bleeder current IB to flow through the bleeder circuit BLD. .

  The drive current control unit 150 controls the drive current ILED of the LED module 10 according to the dimming signal input from the decoder unit 110. Specifically, the drive current control unit 150 generates an on / off control signal for the transistor N1 so that the applied voltage (= ILED × R5) of the external terminal T5 matches a predetermined target value. The target value is set based on the dimming signal input from the decoder unit 110. By setting it as such a structure, it becomes possible to perform dimming control of the LED lighting apparatus 1 using the triac dimmer 40.

  The driver unit 160 amplifies the current capability of the on / off control signal input from the drive current control unit 150 and generates a gate signal of the transistor N1.

<Decoder unit and bleeder control unit>
FIG. 2 is a diagram illustrating a configuration example of the decoder unit 110, the bleeder control unit 140, and the bleeder circuit BLD. The decoder unit 110 of this configuration example includes a comparator 111, a sampling counter 112, a phase angle calculation unit 113, a reference phase angle storage unit 114, and a dimmer presence / absence determination unit 115. The bleeder control unit 140 of this configuration example includes a comparator 141, a driver 142, an N-channel MOS field effect transistor 143, and a control unit 144. The bleeder circuit BLD of this configuration example includes an N-channel MOS field effect transistor N2 and resistors R6 to R8.

  The drain of the transistor N2 is connected to the first output end (application end of the rectified voltage Va) of the diode bridge DB via a resistor R6 (for example, 1 kΩ). The gate of the transistor N2 is connected to the external terminal T2a of the LED driver IC100. The source of the transistor N2 is connected to the external terminal T2b of the LED driver IC 100, and is also connected to the ground terminal via resistors R7 and R8 connected in series. A connection node (application end of the current detection voltage Vc) of the resistors R7 and R8 is connected to the external terminal T2c of the LED driver IC 100, and is also connected to a second output end of the diode bridge DB.

  The comparator 111 compares the rectified voltage Va ′ applied to the non-inverting input terminal (+) with a predetermined threshold voltage Vth1 applied to the inverting input terminal (−) to generate a comparison signal CMP1. The comparison signal CMP1 is at a high level when the rectified voltage Va 'is higher than the threshold voltage Vth1, and conversely, is at a low level when the rectified voltage Va' is lower than the threshold voltage Vth1. The comparison signal CMP1 is sent to the sampling counter 112, and is also sent to the control unit 144 as one of bleeder control signals. The threshold voltage Vth1 may have hysteresis characteristics (for example, threshold voltage when the comparison signal CMP1 is raised to a high level: 420 mV, threshold voltage when the comparison signal CMP1 is lowered to a low level: 300 mV) ).

  The sampling counter 112 measures the high level period TH and the low level period TL of the comparison signal CMP1. The high level period TH can be obtained by measuring the period from the rising edge to the falling edge of the comparison signal CMP1. The low level period TL can be obtained by measuring the period from the falling edge to the rising edge of the comparison signal CMP1.

  FIG. 3 is a diagram illustrating an operation example of the comparator 111 and the sampling counter 112, in which voltage waveforms of the rectified voltage Va ′ and the comparison signal CMP1 are depicted in order from the top.

  The phase angle calculation unit 113 calculates the phase angle S1 (digital value) of the rectified voltage Va ′ for each period based on the output (TH, TL) of the sampling counter. Since the phase angle S1 of the rectified voltage Va ′ corresponds to on-duty (= TH / (TH + TL)), the phase angle calculation unit 113 can also be understood as a duty calculation unit.

  The reference phase angle storage unit 114 stores a predetermined reference phase angle S2 (digital value) to be compared with the phase angle S1. As the reference phase angle storage unit 114, a non-volatile memory such as a ROM [Read Only Memory] or a flash memory can be used.

  The dimmer presence / absence determination unit 115 determines the presence / absence of the triac dimmer 40 by comparing the phase angle S1 of the rectified voltage Va ′ with a predetermined reference phase angle S2, and the presence / absence of the dimmer according to the determination result. The determination signal S3 is sent to the control unit 144 as one of bleeder control signals.

  FIG. 4 is a diagram illustrating a setting example of the reference phase angle S2. When the triac dimmer 40 is not provided, the phase angle S1 of the rectified voltage Va 'is 180 deg. (100%). On the other hand, when the triac dimmer 40 is provided, the phase angle S1 of the rectified voltage Va ′ is 135 deg. (75%) only increases to the extent. Therefore, by setting the reference phase angle S2 to an appropriate value (for example, 150 to 160 deg.), Based on the comparison result between the phase angle S1 of the rectified voltage Va ′ and the reference phase angle S2, the triac dimmer 40 The presence or absence can be determined.

  Specifically, the dimmer presence / absence determination unit 115 determines that the triac dimmer 40 is provided when the phase angle S1 of the rectified voltage Va ′ is smaller than the reference phase angle S2, and the rectified voltage Va. When the phase angle S1 of 'is larger than the reference phase angle S2, it is determined that the triac dimmer 40 is not provided. The dimmer presence / absence determination signal S3 is at a high level when a determination is made that there is a dimmer, and is at a low level when a determination without a dimmer is made.

  The comparator 141 compares the current detection voltage Vc applied to the inverting input terminal (−) and a predetermined threshold voltage Vth2 applied to the non-inverting input terminal (+) to generate a comparison signal CMP2. The current detection voltage Vc is a negative voltage that decreases as the current Isup flowing through the resistor R8 increases and increases as the current Isup decreases. The comparison signal CMP2 becomes high level when the current Isup flowing through the resistor R8 is larger than the threshold current and the current detection voltage Vc is lower than the threshold voltage Vth2, and conversely, the current Isup flowing through the resistor R8 is smaller than the threshold current. When the current detection voltage Vc is higher than the threshold voltage Vth2, it becomes low level. The comparison signal CMP2 is sent to the control unit 144. The threshold voltage Vth2 should have hysteresis characteristics (for example, threshold voltage when the comparison signal CMP2 is raised to a high level: −100 mV, threshold voltage when the comparison signal CMP2 is lowered to a low level: −50 mV).

  The driver 142 amplifies the current capability of the on / off control signal input from the control unit 144 and generates the gate signal of the transistor N2 from the external terminal T2a.

  The transistor 143 conducts / cuts off between the external terminal T2b and the ground terminal in accordance with an on / off control signal input from the control unit 144.

  The control unit 144 performs enable control of the bleeder circuit BLD according to the dimmer presence / absence determination signal S3. Specifically, the control unit 144 enables the bleeder circuit BLD according to the determination result with the dimmer (S3: high level), and according to the determination result without the dimmer (S3: low level). The bleeder circuit BLD is disabled. Note that when the bleeder circuit BLD is in a disabled state, the transistor N2 is always turned off regardless of the comparison signals CMP1 and CMP2. With such a configuration, when the TRIAC dimmer 40 is not provided, it is possible to stop the bleeder current IB and suppress waste of power.

  In addition, when the control unit 144 enables the bleeder circuit BLD according to the determination result with the dimmer, the bleeder control mode switching process (strong bleeder / weak bleeder / off) according to the comparison signals CMP1 and CMP2. I do. This point will be described in detail later.

  FIG. 5 is a flowchart illustrating an example of a dimmer presence / absence determination operation. When the flow starts, first, in step S101, power-on determination of the LED driver IC 100 (for example, confirmation of the logic level of the reduced voltage protection signal) is performed. If the determination is yes, the flow proceeds to step S102 and the LED driver IC 100 is activated. On the other hand, when a negative determination is made, the power-on determination is continued.

  After activation of the LED driver IC 100, in step S103, the dimmer presence / absence determining unit 115 determines whether or not the relational expression S1 ≦ S2 is satisfied. If the determination is yes, it is determined that there is a dimmer, and the flow proceeds to step S104. On the other hand, if a negative determination is made, it is determined that there is no dimmer and the flow proceeds to step S106.

  If it is determined in step S103 that there is a dimmer, the bleeder circuit BLD is enabled in step S104, and a bleeder control mode switching process is performed. Thereafter, in step S105, the power-off determination of the LED driver IC 100 (for example, confirmation of the logic level of the reduced voltage protection signal) is performed. If the determination is no, the flow returns to step S104 and the bleeder control mode switching process is continued. On the other hand, if a yes determination is made, the flow returns to step S101, and the process proceeds to the power-on determination of the LED driver IC 100 described above.

  On the other hand, if it is determined in step S103 that there is no dimmer, the bleeder circuit BLD is disabled in step S106, and the bleeder current IB is stopped. Thereafter, in step S107, the power-off determination of the LED driver IC 100 (for example, confirmation of the logic level of the reduced voltage protection signal) is performed. Here, when a negative determination is made, the flow is returned to step S103, and the presence / absence of the triac dimmer 40 is determined again. On the other hand, if a yes determination is made, the flow returns to step S101, and the process proceeds to the power-on determination of the LED driver IC 100 described above.

  As described above, the dimmer presence / absence determination unit 115 maintains the determination result for the determination result with the dimmer until the power of the LED driver IC 100 is turned off, while the determination result without the dimmer With respect to the above, even if the power of the LED driver IC 100 is not turned off, the determination of the presence or absence of the triac dimmer 40 is periodically repeated without maintaining the determination result.

  With such a configuration, when it is possible to set a phase angle S1 larger than the reference phase angle S2 using the triac dimmer 40, an erroneous determination without a dimmer is once performed. Even if it is, the correct determination with the dimmer can be made again when the phase angle S1 smaller than the reference phase angle S2 is set. However, when the reference phase angle S2 is set to a sufficiently large value (for example, in the vicinity of 180 deg. (100%)), when no determination is made in step S107, the flow is returned to step S106 ( (See the dashed arrow in FIG. 5).

<Bleeder control mode switching process>
FIG. 6 is a diagram showing a first switching example (with a dimmer) in the bleeder control mode. In order from the top, the rectified voltage Va ′, the comparison signal CMP1, the current detection voltage Vc, the comparison signal CMP2, and the bleeder The control mode is depicted. For the sake of simplicity, it is assumed in FIG. 6 that no hysteresis characteristic is given to the threshold voltages Vth1 and Vth2.

  When the triac dimmer 40 is provided and the relational expression S1 ≦ S2 is satisfied, the control unit 144 enables the bleeder circuit BLD according to the determination result (S3: high level) with the dimmer. The bleeder control mode switching process (on / off control of the transistors N2 and 143) is performed in accordance with the comparison signals CMP1 and CMP2.

  Specifically, the control unit 144 turns on both the transistor N2 and the transistor 143 during a period in which the comparison signal CMP1 is at a low level, that is, a period in which the rectified voltage Va ′ is lower than the threshold voltage Vth1. . This operation state corresponds to a state where the bleeder control mode is set to the strong bleeder mode (indicated as “SB [Strong Bleeder]” in FIG. 6). A current flows through the triac dimmer 40 even during the off period of the rectified voltage Va ′. Therefore, if the load connected to the diode bridge DB is large, the rectified voltage Va 'rises during the off period, which may unintentionally exceed the threshold voltage Vth1 and cause a malfunction. On the other hand, if the bleeder control mode is set to the strong bleeder SB during the OFF period of the rectified voltage Va ′, the resistor R6 (for example, 1 kΩ) is connected from the first output terminal (applied terminal of the rectified voltage Va) of the diode bridge DB. The bypass current Ix can be made to flow through the current path to the ground terminal via the via. Accordingly, since the load connected to the diode bridge DB can be made small, it is possible to prevent the rectified voltage Va 'from being lifted during the off period. When the bleeder control mode is set to the strong bleeder SB, the bleeder current IB does not flow from the bleeder circuit BLD to the triac dimmer 40.

  In addition, the control unit 144 turns on the transistor N2 and turns off the transistor 143 in a period in which the comparison signal CMP2 is at a low level even though the comparison signal CMP1 is at a high level. This operation state corresponds to a state where the bleeder control mode is set to the weak bleeder mode (indicated as “WB [Weak Bleeder]” in FIG. 6). That is, in the control unit 144, although the rectified voltage Va ′ is higher than the threshold voltage Vth1, the current Isup flowing through the triac dimmer 40 is lower than the threshold current, and the current detection voltage Vc is higher than the threshold voltage Vth2. In the period, the bleeder circuit BLD is controlled so that the bleeder current IB flows from the bleeder circuit BLD to the triac dimmer 40. Such an operation allows a sufficient holding current to flow through the triac dimmer 40.

  In addition, the control unit 144 turns off both the transistor N2 and the transistor 143 in a period in which the comparison signals CMP1 and CMP2 are both at a high level. This operation state corresponds to a state where the bleeder control mode is set to off-order (indicated as “OFF” in FIG. 6). That is, the control unit 144 is a period in which the rectified voltage Va ′ is higher than the threshold voltage Vth1, and a period in which the current Isup flowing in the triac dimmer 40 is higher than the threshold current (the current detection voltage Vc is higher than the threshold voltage). In the period when the voltage Vth2 is lower), the bleeder circuit BLD is controlled so as to stop the bypass current Ix and the bleeder current IB. By such an operation, when a sufficient current Isup is flowing through the triac dimmer 40, the bypass current Ix and the bleeder current IB can be stopped to suppress waste of power by the bleeder circuit BLD.

  FIG. 7 is a diagram showing a second switching example (no dimmer) in the bleeder control mode. Like FIG. 6, in order from the top, the rectified voltage Va ′, the comparison signal CMP1, the current detection voltage Vc, and the comparison signal are shown. CMP2 and bleeder control mode are depicted. It should be noted that the bleeder control mode with parentheses shown at the bottom is depicted with reference to the state when the bleeder circuit BLD is not disabled.

  When the triac dimmer 40 is not provided and the relational expression S1> S2 is established, the control unit 144 sets the bleeder circuit BLD according to the determination result (S3: low level) without the dimmer. In a disabled state, the bypass current Ix and the bleeder current IB are always stopped without depending on the comparison signals CMP1 and CMP2. This operation state corresponds to a state where the bleeder control mode is set to the above-described off-order (OFF). By adopting such a configuration, when the triac dimmer 40 is not provided, it is possible to stop the bypass current Ix and the bleeder current IB and suppress the waste of power by the bleeder circuit BLD.

<Other variations>
In the above embodiment, the configuration in which the present invention is applied to the LED driver IC has been described as an example. However, the application target of the present invention is not limited to this, and other light emitters (for example, The present invention can be widely applied to all light emitter driving devices that drive organic EL [electro-luminescence]).

  Various technical features disclosed in the present specification can be variously modified within the scope of the technical creation in addition to the above-described embodiment. For example, mutual replacement of a bipolar transistor and a MOS field effect transistor and logic level inversion of various signals are arbitrary. That is, the above-described embodiment is an example in all respects and should not be considered as limiting, and the technical scope of the present invention is not the description of the above-described embodiment, but the claims. It should be understood that all modifications that come within the meaning and range of equivalents of the claims are included.

  The present invention can be suitably used, for example, as a technique for enhancing the versatility of LED driver ICs and LED lighting devices that are compatible with the triac dimming method.

DESCRIPTION OF SYMBOLS 1 LED lighting apparatus 10 LED module 20 Power supply module 30 Commercial alternating current power supply 40 Triac dimmer 100 LED driver IC
DESCRIPTION OF SYMBOLS 110 Decoder part 111 Comparator 112 Sampling counter 113 Phase angle calculation part 114 Reference | standard phase angle storage part 115 Dimmer presence / absence determination part 120 Voltage drop protection part (UVLO part)
130 regulator unit 140 bleeder control unit 141 comparator 142 driver 143 N-channel MOS field effect transistor 144 control unit 150 drive current control unit 160 driver unit DB diode bridge BLD bleeder circuit R1 to R8 resistor D1 to D4 diode ZD Zener diode C1 to C3 Capacitor Q1 npn type bipolar transistor N1, N2 N channel type MOS field effect transistor TR transformer L1 primary winding L2 secondary winding

Claims (8)

A dimmer presence / absence determining unit that compares the phase angle of the rectified voltage with a predetermined reference phase angle to determine the presence or absence of the dimmer;
A bleeder control unit that performs enable control of the bleeder circuit according to the determination result of the dimmer presence / absence determination unit;
I have a,
The dimmer presence / absence determination unit maintains the dimming presence / absence determination result, while the dimming / non-dimming determination result maintains the dimming presence / absence determination periodically. A light emitting device driving device characterized by repeating .   The dimmer presence / absence determining unit determines that there is a dimmer when the phase angle of the rectified voltage is smaller than the reference phase angle, and adjusts when the phase angle of the rectified voltage is larger than the reference phase angle. The light emitter driving apparatus according to claim 1, wherein it is determined that there is no optical device.   The bleeder control unit enables the bleeder circuit according to a determination result with a dimmer, and disables the bleeder circuit according to a determination result without a dimmer. 2. The light emitter driving device according to 2. A dimmer presence / absence determining unit that compares the phase angle of the rectified voltage with a predetermined reference phase angle to determine the presence or absence of the dimmer;
A bleeder control unit that performs enable control of the bleeder circuit according to the determination result of the dimmer presence / absence determination unit;
Have
The dimmer presence / absence determining unit determines that there is a dimmer when the phase angle of the rectified voltage is smaller than the reference phase angle, and adjusts when the phase angle of the rectified voltage is larger than the reference phase angle. Judge that there is no light,
The bleeder controller is
The bleeder circuit is enabled according to the determination result with the dimmer, the bleeder circuit is disabled according to the determination result without the dimmer,
When the bleeder circuit is enabled according to the determination result with the dimmer,
In the period when the rectified voltage is lower than the threshold voltage, the bleeder circuit is controlled to flow a bypass current from the application terminal of the rectified voltage toward the ground terminal,
Although the rectified voltage is higher than the threshold voltage, the bleeder circuit is controlled to flow a bleeder current to the dimmer during a period when the current flowing through the dimmer is lower than the threshold current,
The bleeder circuit is controlled to stop the bypass current and the bleeder current in a period in which the rectified voltage is higher than the threshold voltage and a current flowing through the dimmer is higher than the threshold current. on the other hand,
The bleeder circuit when disabled state is always the bypass current and the bleeder current light emission body driving you and controls the bleeder circuit to stop in response to the tone without light controller determination result apparatus. The dimmer presence / absence determination unit maintains the dimming presence / absence determination result, while the dimming / non-dimming determination result maintains the dimming presence / absence determination periodically. The light emitter driving device according to claim 4 , wherein the light emitter driving device is repeated. A comparator that compares the rectified voltage with the threshold voltage to generate a comparison signal;
A sampling counter for measuring a high level period and a low level period of the comparison signal;
A phase angle calculator that calculates the phase angle of the rectified voltage based on the output of the sampling counter;
A reference phase angle storage unit for storing the reference phase angle;
The light-emitting body drive device according to claim 4 , further comprising: A light emitter;
A rectifier circuit that rectifies an alternating voltage to generate the rectified voltage;
A smoothing circuit that generates a DC voltage from the rectified voltage and supplies the DC voltage to the light emitter;
A bleeder circuit that maintains the holding current of the triac dimmer;
A switch element that conducts / cuts off a current path through which the drive current of the light emitter flows; and
The light emitter driving device according to any one of claims 1 to 6, wherein on / off control of the switch element is performed according to a phase angle of the rectified voltage.
A lighting device comprising:   The lighting device according to claim 7, wherein the light emitter includes an LED element.

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