JP2016225268A - Power adjustment circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which: when input voltage is further higher than cut-in voltage, it is difficult to adjust the illumination intensity of a solid-state illuminator because the voltage provided by a driving circuit is not enough to emit the solid-state illuminator.SOLUTION: A power adjusting circuit which generates first driving voltage for driving a first illumination module includes a first power conversion module and a second power conversion module. The first power conversion module generates power supply voltage and second conversion power according to first conversion power. The second power conversion module is electrically connected to the first power conversion module. The second power conversion module converts a part of the second conversion power to first modulation voltage, outputs the first modulation voltage, and adjusts the potential of the first modulation voltage according to a first control signal. The first driving voltage equals the sum of the power supply voltage and the first modulation voltage. The power supply voltage is lower than the cut-in voltage of the first illumination module.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a power conditioning circuit.

  Solid state illuminators such as light emitting diodes (LEDs), organic LEDs and polymer LEDs have a non-linear relationship between input current and input voltage. Specifically, when the drive circuit provides the solid state illuminator with an input voltage that is lower than the cut-in voltage of the solid state illuminator, the solid state illuminator input current is zero. After the drive circuit provides the solid state illuminator with an input voltage higher than the cut-in voltage, the fixed illuminator input current rises rapidly as the input voltage increases.

  When the input voltage is even higher than the cut-in voltage, the voltage provided by the drive circuit is insufficient to cause the solid state illuminator to emit light, and the illumination intensity of the solid state illuminator cannot be adjusted. Therefore, the efficiency level by which the drive circuit adjusts the illumination intensity of the solid state illuminator is lowered, and the light modulation resolution is lowered.

  According to one or more embodiments of the present invention, the present disclosure provides a power conditioning circuit that generates a first drive voltage for driving a first lighting module. In one embodiment of the present invention, the power adjustment circuit includes a first power conversion module and a second power conversion module. The first power conversion module generates a power supply voltage and a second converted power according to the first converted power. The second power conversion module is electrically connected to the first power conversion module. The second power conversion module converts a part of the second converted power into the first modulation voltage, outputs the first modulation voltage, and sets the potential of the first modulation voltage in accordance with the first control signal. adjust. The first drive voltage is equal to the sum of the power supply voltage and the first modulation voltage. The power supply voltage is lower than the cut-in voltage of the first lighting module.

  Therefore, the power adjustment circuit drives the first lighting module with a first drive voltage that is substantially equal to the sum of the power supply voltage and the first modulation voltage. The first drive voltage approaches the cut-in voltage of the first lighting module by the power supply voltage. Therefore, the potential of the first drive voltage becomes higher than the potential of the cut-in voltage of the first lighting module in response to a small portion of the modulation level of the first modulation voltage, and a large portion of the modulation level. In response to changing the illumination intensity of the first illumination module. In this way, the number of modulation levels for adjusting the illumination intensity of the first illumination module is increased, and the light modulation resolution of the first illumination module is improved. Furthermore, the amount of electricity converted by the second power conversion module is reduced, and as a result, power consumption during power conversion is reduced. Therefore, the overall performance of the power adjustment circuit of the present disclosure can be improved.

  The present invention can be more fully understood from the following detailed description and the accompanying drawings. The following detailed description and the accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

It is a block diagram of the power adjustment circuit by one Embodiment of this invention. 6 is a curve graph illustrating a driving voltage to an operating current according to an embodiment of the present invention. 6 is a curve graph illustrating a driving voltage to an operating current according to another embodiment of the present invention. It is a circuit diagram of the power adjustment circuit by one Embodiment of this invention. It is a block diagram of the power adjustment circuit by other embodiment of this invention. It is a circuit diagram of the electric power adjustment circuit by other embodiment of this invention. It is a circuit diagram of the electric power adjustment circuit by other embodiment of this invention.

  In the following detailed description, numerous specific details are set forth for purposes of explanation in order to provide a thorough understanding of the disclosed embodiments, but one or more of the present invention may be practiced without these specific details. It is clear that the embodiment can be implemented. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

  Please refer to FIG. FIG. 1 is a block diagram of a power conditioning circuit 10 according to one embodiment of the present invention. Please refer to FIG. 2 and FIG. 2 and 3 are curve graphs illustrating drive voltage to operating current according to various embodiments. The power adjustment circuit 10 generates a drive voltage VLED that drives the illumination module 30. The power adjustment circuit 10 includes a first power conversion module 11 and a second power conversion module 13. The first power conversion module 11 generates the power supply voltage Vdc and the second converted power P2 according to the first converted power P1. In the present specification, the power supply voltage Vdc is a constant voltage in one embodiment of the present invention, and is a variable voltage in another embodiment. The first converted power P1 is provided by an external power source such as an AC power source 50 or other suitable power source, for example. The first converted power P1 is, for example, the AC voltage Vac, but is not limited thereto. When AC power supply 50 provides AC voltage Vac to first power conversion module 11, first power conversion module 11 converts AC voltage Vac into power supply voltage Vdc and second converted power P2.

  The first power conversion module 11 includes an AC-DC converter 111 and a capacitor 113. The AC-DC converter 111 has a first output end 115 and a second output end 117. The first output terminal 115 and the second output terminal 117 of the AC-DC converter 111 have a potential difference, and the potential difference is equal to the power supply voltage Vdc. Two ends of the capacitor 113 are electrically connected to the first output terminal 115 and the second output terminal 117 of the AC-DC converter 111, and the capacitor 113 is connected to the first output terminal of the AC-DC converter 111. The potential difference between 115 and the second output end 117 can be stabilized. Accordingly, the change in the potential difference between the first output terminal 115 and the second output terminal 117 of the AC-DC converter 111 is relatively small.

  The second power conversion module 13 is electrically connected to the first output end 115 of the AC-DC converter 111. The second power conversion module 13 outputs the second converted power P2 as the modulation voltage Vo, and adjusts the potential of the modulation voltage Vo according to the control signal SC. For example, the second converted power P2 is the input current Iin, and the second power conversion module 13 is a DC-DC converter. In this case, the second power conversion module 13 converts the input current Iin into the modulation voltage Vo and outputs the modulation voltage Vo. The second power conversion module 13 further adjusts the potential of the modulation voltage Vo according to the control signal SC. In one embodiment of the present invention, the second power conversion module 13 adjusts the potential of the modulation voltage Vo by pulse width modulation (PWM) according to the control signal SC. This will be described later.

  The power supply voltage Vdc generated by the first power conversion module 11 and the modulation voltage Vo generated by the second power conversion module 13 are applied to the illumination module 30 so that the illumination module 30 can be driven and its illumination intensity can be adjusted. It has become. In other words, the sum of the power supply voltage Vdc and the modulation voltage Vo is the drive voltage VLED output from the power adjustment circuit 10 to drive the illumination module 30.

  In one embodiment of the invention, the AC-DC converter 111 is implemented by a rectification unit and a DC-DC converter. For example, the DC-DC converter in the AC-DC converter 111 is a boost converter, buck converter, buck-boost converter, flyback converter or other suitable DC-DC converter, and is not limited to any in this disclosure. For example, the second power conversion module 13 is a boost converter, buck converter, buck-boost converter, flyback converter or other suitable DC-DC converter, and is not limited to any in this disclosure.

  In one embodiment of the present invention, as shown in FIG. 2, the power supply voltage Vdc is lower than the cut-in voltage Vf of the lighting module 30. In another embodiment, the power supply voltage Vdc 'is substantially equal to the cut-in voltage Vf of the lighting module 30, as shown in FIG.

  Referring to the curve graph showing the driving voltage to the operating current shown in FIG. 2, when the sum of the adjusted modulation voltage Vo and the power supply voltage Vdc is substantially equal to the cut-in voltage Vf of the lighting module 30, the lighting module 30 Light emission starts, and the operating current ILED of the illumination module 30 changes with the change of the modulation voltage Vo. While the operating current ILED of the lighting module 30 is increasing, the illumination intensity of the lighting module 30 increases in response to the operating current ILED. Therefore, the illumination intensity of the illumination module 30 can be adjusted by adjusting the modulation voltage Vo.

  On the other hand, a person skilled in the art recognizes that the cut-in voltage of the lighting module 30 is usually a threshold voltage for turning on the lighting module 30. Referring to the curve graph showing the driving voltage to the operating current shown in FIG. 3, the threshold voltage for turning on the illumination module 30 is, for example, before and after the cut-in voltage Vf or the cut-in voltage Vf ′, but is not limited thereto. . When the power supply voltage Vdc ′ is substantially equal to the cut-in voltage Vf ′ of the lighting module 30, the operating current ILED flowing through the lighting module 30 is responsive to an increase in the modulation voltage Vo ′ of the second power conversion module 13. As a result, the illumination intensity of the illumination module 30 is adjusted. Therefore, the power supply voltage Vdc ′ is lower than or substantially equal to the cut-in voltage Vf or the cut-in voltage Vf ′ of the lighting module 30.

  In one embodiment of the present invention, the upper limit of the modulation voltage Vo is related to the rated voltage of the lighting module 30, and the rated voltage of the lighting module 30 is the maximum allowable input voltage of the lighting module 30. Specifically, the sum of the upper limit of the modulation voltage Vo and the power supply voltage Vdc is substantially equal to the rated voltage of the lighting module 30. Furthermore, in this embodiment, since the first power conversion module 11 is electrically connected only to the second power conversion module 13, the second power conversion module 13 modulates a part of the second converted power P2. The conversion to the voltage Vo can be considered to be the conversion of the entire second conversion power P2 into the modulation voltage Vo by the second power conversion module 13. In the present specification, the entire second converted power P2 is the remaining portion of the initial second converted power P2, and the second power conversion module 13 is the initial second After a part of the converted power P2 is consumed, it is converted into a modulation voltage Vo. In this specification, the initial second converted power P <b> 2 is the output of the first power conversion module 11.

  The operation of the power adjustment circuit 10 will be clarified as follows by referring to FIG. FIG. 4 is a circuit diagram of the power adjustment circuit 10 according to an embodiment of the present invention. The input terminal of the power adjustment circuit 10 is electrically connected to the AC power supply 50. The output terminal of the power adjustment circuit 10 is electrically connected to the lighting module 30. The output terminal of the power adjustment circuit 10 outputs a drive voltage VLED that drives the illumination module 30.

  The power adjustment circuit 10 includes a first power conversion module 11 and a second power conversion module 13. The first power conversion module 11 includes an AC-DC converter 111 and a capacitor 113. The AC-DC converter 111 includes a rectification unit 1112, a first control unit 1114, a first switching unit 1116, a primary coil Lp, a diode D 1, a resistor R 1, and a resistor R 2. The second power conversion module 13 includes a voltage generation unit 131, a second control unit 133, a second switching unit 135, a diode D2, a capacitor C1, an inductor L1, and a resistor R3.

  The rectification unit 1112 rectifies the AC voltage Vac provided by the AC power supply 50 and generates DC supply power. When the first switching unit 1116 is turned on by the control of the first control unit 1114, the rectifying unit 1112 outputs DC supply power to the primary coil Lp and the capacitor 113, which is output to the primary coil Lp and the capacitor 113. To store. When the first switching unit 1116 is turned on by the control of the first control unit 1114, the electricity stored in the primary coil Lp is discharged to the resistors R1 and R2, and the capacitor 113 is a series circuit of the resistors R1 and R2. Is maintained at the power supply voltage Vdc.

  When a current flows in the primary coil Lp in the first power conversion module 11, the secondary coil Ls in the second power conversion module 13 outputs an input current Iin based on mutual electromagnetic induction. The voltage generation unit 131 of the second power conversion module 13 generates an input voltage according to the input current Iin. When the second switching unit 135 is turned on in response to the control of the second control unit 133, the input voltage Vin charges the capacitor C1 and the inductor L1. When the second switching unit 135 is switched off in response to the control of the second control unit 133, the energy stored in the inductor L1 and the capacitor C1 is released, thereby causing the second power conversion module 13 to The voltage difference between the two ends of the capacitor C1 becomes the modulation voltage Vo.

  In other words, when the first switching unit 1116 in the AC-DC converter 111 is switched on, the AC power supply 50 supplies the AC voltage Vac to the rectifying unit 1112 and the rectifying unit 1112 is electrically connected via the current path PI1. Is output. When the first switching unit 1116 is switched off, the energy stored in the primary coil Lp is released through the current path PI2. The AC-DC converter 111 controls switching of the first switching unit 1116 to set the average voltage difference between the node N1 and the node N2 to the power supply voltage Vdc.

  In the second power conversion module 13, when the second switching unit 135 is switched on, the voltage generation unit 131 outputs electricity via the current path PI3. When the second switching unit 135 is switched off, the electricity stored in the inductor L1 is discharged through the current path PI4. The second power conversion module 13 controls switching of the second switching unit 135 and sets the average voltage difference between the node N3 and the node N4 to the modulation voltage Vo.

  Since the lighting module 30 is electrically connected to each of the nodes N2 and N4, the lighting module 30 is driven by a voltage difference between the nodes N2 and N4. That is, the voltage difference between the nodes N2 and N4 is substantially equal to the sum of the power supply voltage Vdc generated by the AC-DC converter 111 and the modulation voltage Vo generated by the second power conversion module 13. The sum of the power supply voltage Vdc and the modulation voltage Vo acts as a drive voltage VLED that drives the illumination module 30.

  In one embodiment of the present invention, the modulation voltage Vo by PWM is adjusted by the second control unit 133 after the control signal SC is applied to the second control unit 133 according to the control signal SC. Is to adjust. For example, the control signal SC is an 8-bit binary signal, a 32-bit hexadecimal signal, or another suitable type of signal.

  One or more embodiments described below are based on a control signal SC having 8 bits, where the control signal SC controls the second power conversion module 13 by providing 256 levels of optical modulation to modulate the modulation voltage. The potential of Vo is adjusted.

  In one embodiment of the present invention, levels 0 to 35 of the control signal SC are not sufficient to cause the lighting module 30 to emit light, the sum of the modulation voltage Vo and the power supply voltage Vdc generated by the second control unit 133. It shows that. At the level 36 or higher of the control signal SC, the sum of the modulation voltage Vo and the power supply voltage Vdc drives the lighting module 30 to emit light. In other words, the sum of the modulation voltage Vo and the power supply voltage Vdc is sufficient to cause the illumination module 30 to emit light in response to the levels 36 to 256 of the control signal SC, and the illumination intensity of the illumination module 30 is equal to the control signal SC. It changes according to the level change.

  Specifically, when the control signal SC is level 0, the modulation voltage Vo generated by the second power conversion module 13 is about 0 volts (V), and the operating current ILED flowing through the lighting module 30 is about 0. Ampere (A). When the control signal SC is at level 36, the operating current ILED flowing through the lighting module 30 begins to rise. When the control signal SC is at level 256, the modulation voltage Vo generated by the second power conversion module 13 is about 10V, so that the operating current ILED flowing in the lighting module 30 is at its maximum value, for example 0.3A. Reach. Therefore, the effective level number of light modulation provided by the control signal SC is about 220, and the voltage to be modulated at each level is about 0.045V. That is, the least significant bit (LSB) of the control signal SC corresponds to 0.45% of the voltage adjustment range.

  Alternatively, the operating current ILED flowing through the illumination module 30 starts to increase when the control signal SC is at level 0, and the modulation voltage Vo generated by the second power conversion module 13 when the control signal SC is at level 256 is about 10V. The operating current ILED flowing through the lighting module 30 is about 0.3A. In this case, the number of efficient levels of light modulation provided by the control signal SC is about 256, and the voltage to be modulated at each level is about 0.039V. The LSB of the control signal SC corresponds to 0.39% of the voltage adjustment range, so that the resolution of the light modulation is better.

  In the adjustment of the modulation voltage Vo in another embodiment, in addition to transmitting the control signal SC to the second control unit 133, the second control unit 133 adjusts the potential of the modulation voltage Vo according to the feedback signal SR. To be executed. In this specification, the feedback signal SR is related to the modulation voltage Vo. Referring to the circuit shown in FIG. 4, the feedback signal SR is generated by the voltage difference between the two ends of the resistor R3. Since the current flowing in the capacitor C1 also flows in the resistor R3, the current flowing in the capacitor C1 causes a modulation voltage Vo between the two ends of the capacitor C1. Furthermore, such a current causes a voltage difference between the two ends of resistor R3. Therefore, the feedback signal SR is related to the potential of the modulation voltage Vo. The second control unit 133 adjusts the next potential of the modulation voltage Vo according to the current potential of the modulation voltage Vo by detecting the voltage difference between the two ends of the register R3, and The potential specifies the value of the control signal SC.

  On the other hand, the first control unit 1114 in the first power conversion module 11 can also adjust the potential of the power supply voltage Vdc according to the feedback signal SF. As shown in FIG. 4, the feedback signal SF is a divided voltage at the junction node of the resistors R1 and R2 to which the output of the capacitor C1 is applied. Specifically, feedback signal SF is a voltage at the junction node of registers R1 and R2 when power supply voltage Vdc is applied to the series circuit of registers R1 and R2. The first power conversion module 11 can know the current potential of the power supply voltage Vdc via the feedback signal SF in order to adjust the power supply voltage Vdc.

  In the present embodiment or some embodiments, there are various methods for realizing the generation of the feedback signal SF by the first power conversion module 11 and the generation of the feedback signal SR by the second power conversion module 13. Furthermore, the need to generate the feedback signal SF and the feedback signal SR can be designed according to the actual application requirements. In other words, the first control unit 1114 can operate without the feedback signal SF, and the second control unit 133 can operate without the feedback signal SR.

  Please refer to FIG. FIG. 5 is a block diagram of a power adjustment circuit 20 according to another embodiment. The power adjustment circuit 20 generates the first drive voltage VLED1 and the second drive voltage VLED2, and drives the first illumination module 40 and the second illumination module 60. The power adjustment circuit 20 includes a first power conversion module 21, a second power conversion module 23, and a third power conversion module 25. The first power conversion module 21 generates the power supply voltage Vdc_0 and the second converted power P2_0 according to the first converted power P1_0 supplied by the external AC power supply 80.

  The power adjustment circuit 20 is similar to the power adjustment circuit 10 of FIG. The first power conversion module 21 includes an AC-DC converter 211 and a capacitor 213. The AC-DC converter 211 has a first output end 215 and a second output end 217. The voltage difference between the first output terminal 215 and the second output terminal 217 of the AC-DC converter 211 is the power supply voltage Vdc_0. Two ends of the capacitor 213 are electrically connected to the first output terminal 215 and the second output terminal 217, respectively. The capacitor 213 stabilizes the potential difference between the first output terminal 215 and the second output terminal 217, whereby the potential difference between the first output terminal 215 and the second output terminal 217 changes relatively. small.

  However, the first output terminal 215 of the AC-DC converter 211 is electrically connected not only to the second power conversion module 23 but also to the third power conversion module 25. Therefore, a part of the second converted power P2_0 generated by the first power conversion module 21 is supplied to the second power conversion module 23, and the other part of the second converted power P2_0 is the third power conversion module. 25.

  The second power conversion module 23 converts a part of the second converted power P2_0 into the first modulation voltage Vo1, and adjusts the potential of the first modulation voltage Vo1 according to the first control signal SC1. The third power conversion module 25 converts the other part of the second converted power P2_0 into the second modulation voltage Vo2, and adjusts the potential of the second modulation voltage Vo2 according to the second control signal SC2. .

  The power supply voltage Vdc_0 generated by the first power conversion module 21 and the first modulation voltage Vo1 output by the second power conversion module 23 are supplied to the first lighting module 40, and the first lighting module 40 It is designed to be driven. The illumination intensity of the first illumination module 40 is controlled by adjusting the first modulation voltage Vol. The power supply voltage Vdc_0 generated by the first power conversion module 21 and the second modulation voltage Vo2 output by the third power conversion module 25 are supplied to the second lighting module 60, and the second lighting module 60 It is designed to be driven. Adjusting the second modulation voltage Vo2 affects the illumination intensity of the second illumination module 60. In other words, the sum of the power supply voltage Vdc_0 and the first modulation voltage Vo1 is the first drive voltage VLED1 output by the power adjustment circuit 20 to drive the first illumination module 40. Furthermore, the sum of the power supply voltage Vdc_0 and the second modulation voltage Vo2 is the second drive voltage VLED2 output by the power adjustment circuit 20 to drive the second illumination module 60.

  In the present embodiment, the power supply voltage Vdc_0 output from the first power conversion module 21 is lower than the cut-in voltage Vf1 of the first lighting module 40 and the cut-in voltage Vf2 of the second lighting module 60. When the total of the first modulation voltage Vo1 is adjusted and the power supply voltage Vdc / 0 becomes substantially equal to the cut-in voltage Vf1 of the first lighting module 40, the first lighting module 40 starts to emit light. While the first modulation voltage Vo1 changes, the first operating current ILED1 flowing through the first lighting module 40 also changes, and as a result, the illumination intensity of the first lighting module 40 changes. When the sum of the second modulation voltage Vo2 and the power supply voltage Vdc_0 is substantially equal to the cut-in voltage Vf2 of the second lighting module 60, the second lighting module 60 starts to emit light. While the second modulation voltage Vo2 changes, the second operating current ILED2 flowing through the second lighting module 60 also changes, and as a result, the illumination intensity of the second lighting module 60 changes.

  In one embodiment of the present invention, the upper limit of the first modulation voltage Vo1 is related to the rated voltage of the first lighting module 40, and the rated voltage of the first lighting module 40 is the maximum of the first lighting module 40. Allowable input voltage. The upper limit of the second modulation voltage Vo2 is related to the rated voltage of the second lighting module 60, and the rated voltage of the second lighting module 60 is the maximum allowable input voltage of the second lighting module 60. Specifically, the sum of the upper limit of the first modulation voltage Vo1 and the power supply voltage Vdc_0 is substantially equal to the rated voltage of the first lighting module 40, and the sum of the upper limit of the second modulation voltage Vo2 and the power supply voltage Vdc_0. Is substantially equal to the rated voltage of the second lighting module 60.

  In an ideal operation, the second converted power P2_0 generated by the first power conversion module 21 is the sum of the output power value of the second power conversion module 23 and the output power value of the third power conversion module 25. Has a power value substantially equal to. However, in actual operation, power is consumed for the conversion of electricity, so that the power value of the second converted power P2_0 is the output power value of the second power conversion module 23 and the output of the third power conversion module 25. It may not be equal to the sum of the power values. In the present disclosure, such an error in the power value is allowed.

  Furthermore, in one embodiment of the present invention, the maximum converted power value of the second power conversion module 23 or the maximum converted power value of the third power conversion module 25 is substantially equal to the power value of the second converted power P2_0. . For example, the power value of the second converted power P2_0 generated by the first power conversion module 21 is about 20 watts (W), and 15 W of the second converted power P2_0 is equal to the first lighting module 40 and the second power This acts as the power supply voltage Vdc_0 to the second lighting module 60. A part of 5W of the second converted power P2_0 is supplied to the second power conversion module 23 for power conversion, and the other part of 5W of the second converted power P2_0 is a third power conversion for power conversion. The module 25 is supplied. In this case, the maximum output power value of the second power conversion module 23 and the maximum output power value of the third power conversion module 25 may be 5W. Therefore, both the second power conversion module 23 and the third power conversion module 25 employ a converter that supports a maximum converted power value of 5 W. In other words, since the power capacity required by the second power conversion module 23 and the third power conversion module 25 is small, the power consumption during power conversion can be reduced, and the second power conversion module 23 and the third power conversion module 23 can be reduced. The capacity occupied by the power conversion module 25 may also be reduced. Such an embodiment based on the second converted power P2_0 having a power value of 20 W and the second power conversion module 23 and the third power conversion module 25 having a maximum output power value of 5 W Although this is an example for explaining the disclosure, the present disclosure is not limited thereto.

  In one or more embodiments of the present invention, the first lighting module 40 and the second lighting module 60 are implemented by the same or different amounts of LEDs that emit light of the same or different colors.

  In one embodiment of the present invention, the first control signal SC1 for controlling the second power conversion module 23 and the second control signal SC2 for controlling the third power conversion module 25 are the desired illumination intensity, color, Depending on the color temperature or other requirements, provided by the same or different controller.

  In one embodiment of the present invention, the second power conversion module 23 and the third power conversion module 25 receive different percentages of the second converted power P2_0, and then the first control signal SC1 and the second Different first modulation voltage Vo1 and second modulation voltage Vo2 in response to the control signal SC2. In other embodiments, the second power conversion module 23 and the third power conversion module 25 receive the same percentage of the second converted power P2_0, and the first control signal SC1 and the second control signal, respectively. Different modulation voltages Vo1 and Vo2 are output in response to SC2. Therefore, the first driving voltage VLED1 supplied to the first lighting module 40 and the second driving voltage VLED2 supplied to the second lighting module 60 are different from each other. The illumination intensity of the two illumination modules 60 is also different from each other.

  In an embodiment of the present invention, the light emitted by the first lighting module 40 and the light emitted by the second lighting module 60 are mixed to form mixed light having a certain color temperature or color, or Separated from each other.

  Please refer to FIG. FIG. 6 is a circuit diagram of a power adjustment circuit 20a according to another embodiment. The input terminal of the power adjustment circuit 20a is electrically connected to the AC power source 80a. The first output terminal of the power adjustment circuit 20a is electrically connected to the first lighting module 40a, and the second output terminal of the power adjustment circuit 20a is electrically connected to the second lighting module 60a. Yes. The first output terminal of the power adjustment circuit 20a outputs the first drive voltage VLED_1a that drives the first illumination module 40a, and the second output terminal of the power adjustment circuit 20a drives the second illumination module 60a. The second drive voltage VLED_2a is output.

  The power adjustment circuit 20a includes a first power conversion module 21a, a second power conversion module 23a, and a third power conversion module 25a. The first power conversion module 21a includes an AC-DC converter 211a and a capacitor 213a. The AC-DC converter 211a includes a rectifying unit 2112a, a first control unit 2114a, a first switching unit 2116a, a primary coil Lp_1a, a primary coil Lp_2a, a diode D3_a, a diode D4_a, and a capacitor C2_a. And a register R4_a and a register R5_a. The second power conversion module 23a includes a voltage generation unit 231a, a second control unit 233a, a second switching unit 235a, a diode D5, a capacitor C3, an inductor L2, and a resistor R6. The third power conversion module 25 includes a voltage generation unit 251a, a second control unit 253a, a second switching unit 255a, a diode D6, a capacitor C4, an inductor L3, and a resistor R7.

  The rectification unit 2112a rectifies the AC voltage Vac_a provided by the AC power supply 80a, and outputs DC supply electricity. When the first switching unit 2116a is turned on in response to the control of the first control unit 2114a, the DC electricity output from the rectifying unit 2112a is transferred to the primary coil Lp_1a, the primary coil Lp_2a, the capacitor 213a, and the capacitor C2_a. Supplied and stored in primary coil Lp_1a, primary coil Lp_2a, capacitor 213a and capacitor C2_a. When the first switching unit 2116a is turned off in response to the control of the first control unit 2114a, the energy stored in the primary coil Lp_1a is released to the resistors R4_a and R5_a and stored in the capacitor 213a. Energy maintains the voltage difference between the two ends of the series circuit of resistors R4_a and R5_a. Therefore, the voltage difference between the two ends of the series circuit of the resistors R4_a and R5_a has a relatively small change. The AC-DC converter 211a employs switching on / off of the first switching unit 2116a, and sets the average voltage difference between the two ends of the capacitor 213a to the power supply voltage Vdc_a. On the other hand, when the first switching unit 2116a is turned off in response to the control of the first control unit 2114a, the primary coil Lp_2a, the capacitor C2_a, and the diode D4_a form another loop path, and the primary coil Lp_2a. And the capacitor C2_a release the energy stored in itself, whereby a current flows in the primary coil Lp_2a.

  When a current flows in the primary coil Lp_1a and the primary coil Lp_2a in the first power conversion module 21a, the secondary coil Ls_1a in the second power conversion module 23a generates an input current I1_a under mutual electromagnetic induction. The secondary coil Ls_2a in the third power conversion module 25a generates the input current I2_a. In the present embodiment, the primary coil Lp_1a and the secondary coil Ls_1a in the second power conversion module 23a are paired, and the primary coil Lp_2a and the secondary coil Ls_2a in the third power conversion module 25a are paired. Become. Alternatively, the primary coil Lp_1a and the secondary coil Ls_2a in the third power conversion module 25a are paired, and the primary coil Lp_2a and the secondary coil Ls_1a in the second power conversion module 23a are paired.

  The voltage generation unit 231a in the second power conversion module 23a generates the input voltage V1_a according to the input current I1_a. When the second switching unit 235a is turned on in response to the control of the second control unit 233a, the input voltage V1_a charges the capacitor C3 and the inductor L2, and as a result, in the second power conversion module 23a. A voltage difference is generated between the two ends of the capacitor C3. When the second switching unit 235a switches off in response to the control of the second control unit 233a, the inductor L2 and the capacitor C3 release the energy stored in itself, so that the second power conversion module A voltage difference occurs between the two ends of the capacitor C3 in 23a. The second power conversion module 23a employs switching on / off of the second switching unit 235a to set the average voltage difference between the two ends of the capacitor C3 to the first modulation voltage Vo_1a.

  The voltage generation unit 251a in the third power conversion module 25a generates the input voltage V2_a according to the input current I2_a. When the second switching unit 255a switches on in response to the control of the second control unit 253a, the input voltage V2_a charges the capacitor C4 and the inductor L3, thereby causing a voltage across the two ends of the capacitor C4. There is a difference. When the second switching unit 255a switches off in response to the control of the second control unit 253a, the inductor L3 and the capacitor C4 release the energy stored in itself, and as a result, the two ends of the capacitor C4. A voltage difference occurs between the parts. The third power conversion module 25a employs switching on / off of the second switching unit 235a to set the average voltage difference between the two ends of the capacitor C4 to the second modulation voltage Vo_2a.

  The power supply voltage Vdc_a generated by the first power conversion module 21a and the first modulation voltage Vo_1a generated by the second power conversion module 23a are both supplied to the first lighting module 40a to be supplied to the first lighting module 40a. Drive. Furthermore, the illumination intensity of the first illumination module 40a is controlled by adjusting the first modulation voltage Vo_1a. Specifically, the two end portions of the first lighting module 40a are electrically connected to the node N5_a and the node N6_a, respectively. The voltage difference between the node N5_a and the node N6_a is substantially equal to the sum of the power supply voltage Vdc_a and the first modulation voltage Vo_1a, and acts as a first drive voltage VLED_1a that drives the first lighting module 40a.

  The power supply voltage Vdc_a generated by the first power conversion module 21a and the second modulation voltage Vo_2a generated by the third power conversion module 25a are both supplied to the second lighting module 60a to be supplied to the second lighting module 60a. Drive. Furthermore, the illumination intensity of the second illumination module 60a is controlled by adjusting the second modulation voltage Vo_2a. Specifically, the two end portions of the second lighting module 60a are electrically connected to the node N5_a and the node N7_a, respectively. The voltage difference between the node N5_a and the node N7_a is substantially equal to the sum of the power supply voltage Vdc_a and the second modulation voltage Vo_2a, and acts as a second drive voltage VLED_2a that drives the second lighting module 60a.

  In the present embodiment, the power supply voltage Vdc_a generated by the first power conversion module 21a is lower than the cut-in voltage Vf_1a of the first lighting module 40a and the cut-in voltage Vf_2a of the second lighting module 60a.

  In one embodiment of the present invention, the second control unit 233a adjusts the potential of the first modulation voltage Vo_1a according to the first control signal SC_1a and the first feedback signal SR_1a. The first feedback signal SR_1a is related to the potential of the first modulation voltage Vo_1a. For example, the first feedback signal SR_1a is executed by the voltage difference between the two ends of the resistor R6 as shown in FIG. The second control unit 233a can obtain the current potential of the first modulation voltage Vo_1a by detecting the voltage difference between the two ends of the resistor R6, and the second control unit 233a can obtain the current potential of the first modulation voltage Vo_1a. The electric potential is adjusted. Therefore, the potential of the first modulation voltage Vo_1a can be adapted to the value of the first control signal SC_1a.

  The second control unit 253a adjusts the potential of the second modulation voltage Vo_2a according to the second control signal SC_2a and the second feedback signal SR_2a. The second feedback signal SR_2a is related to the potential of the second modulation voltage Vo_2a. For example, the second feedback signal SR_2a is executed by a voltage difference between the two ends of the resistor R7 as shown in FIG. The second control unit 253a detects the voltage difference between the two ends of the resistor R7, thereby obtaining the current potential of the second modulation voltage Vo_2a and adjusting the next potential of the second modulation voltage Vo_2a. It is supposed to be. Therefore, the potential of the second modulation voltage Vo_2a can be adapted to the value of the second control signal SC_2a.

  In one embodiment of the present invention, the first control unit 2114a in the first power conversion module 21a adjusts the potential of the power supply voltage Vdc_a according to the feedback signal SF_a. The adjustment of the potential of the power supply voltage Vdc_a in accordance with the feedback signal SF_a can be referred to as the related operation in FIG. 4 and will not be repeated below.

  Please refer to FIG. FIG. 7 is a circuit diagram of a power adjustment circuit 20b according to another embodiment. The power adjustment circuit 20b includes a first power conversion module 21b, a second power conversion module 23b, and a third power conversion module 25b. The first power conversion module 21b is substantially equivalent to the first power conversion module 21a of FIG.

  However, the second power conversion module 23b and the third power conversion module 25b in FIG. 7 are different from the second power conversion module 23a and the third power conversion module 25b in FIG. The second power conversion module 23b includes a voltage generation unit 231b, a second control unit 233b, a second switching unit 235b, a primary coil Np1, a secondary coil Ns1, a diode D7, and a capacitor C5. including. The third power conversion module 25b includes a voltage generation unit 251b, a second control unit 253b, a second switching unit 255b, a primary coil Np2, a secondary coil Ns2, a diode D8, and a capacitor C6. including.

  When a current flows through the primary coil Lp_1b and the primary coil Lp_2b in the first power conversion module 21b, the secondary coil Ls_1b in the second power conversion module 23b generates an input current I1_b under mutual electromagnetic induction, The secondary coil Ls_2b in the third power conversion module 25b generates the input current I2_b.

  The voltage generation unit 231b in the second power conversion module 23b generates the input voltage V1_b according to the input current Il_b. When the second switching unit 235b is turned on in response to the control of the second control unit 233b, the voltage generation unit 231b, the second control unit 233b, and the primary coil Np1 form a loop path, and the primary A current is formed on the coil Np1. Under mutual electromagnetic induction, the secondary coil Ns1 generates an induced current in response to the current flowing in the primary coil Np1, and as a result, a voltage difference is generated between the two ends of the capacitor C5. When the second switching unit 235b switches off in response to the control of the second control unit 233b, the secondary coil Ns1 releases the energy stored in itself, thereby between the two ends of the capacitor C5. There is a voltage difference between the two. The second power conversion module 23b adopts switching on / off of the second switching unit 235b to set the average voltage difference between the two ends of the capacitor C5 to the first modulation voltage Vo_1b, and the capacitor C5 This acts to suppress a change in potential of the first modulation voltage Vo_1b.

  The voltage generation unit 251b in the third power conversion module 25b generates the input voltage V2_b according to the input current I2_b. When the second switching unit 255b is turned on in response to the control of the second control unit 253b, the voltage generation unit 251b, the second control unit 253b, and the primary coil Np2 form a loop path, and the primary A current is formed on the coil Np2. Under mutual electromagnetic induction, the secondary coil Ns2 generates an induced current, and a voltage difference is generated between the two ends of the capacitor C6. When the second switching unit 255b switches off in response to the control of the second control unit 253b, the secondary coil Ns2 releases the energy stored in itself, and a voltage is applied between the two ends of the capacitor C6. There is a difference. The third power conversion module 25b employs switching on / off of the second switching unit 255b to set the average voltage difference between the two ends of the capacitor C6 to the second modulation voltage Vo_2b, and the capacitor C6 The second modulation voltage Vo_2b acts to suppress a change in potential.

  In the second power conversion module 23b, the second control unit 233b controls the ON period of the second switching unit 235b, the number of turns of the primary coil Np1, and the number of turns of the secondary coil Ns1. The potential of one modulation voltage Vo_1b is adjusted. Further, in the third power conversion module 25b, the second control unit 253b controls the ON period of the second switching unit 255b, the number of turns of the primary coil Np2, and the number of turns of the secondary coil Ns2. The potential of the second modulation voltage Vo_2b is adjusted.

  The power supply voltage Vdc_b generated by the first power conversion module 21b and the first modulation voltage Vo_1b generated by the second power conversion module 23b are both supplied to the first lighting module 40b to be supplied to the first lighting module 40b. Drive. The first modulation voltage Vo_1b is adjusted to control the illumination intensity of the first illumination module 40b. Specifically, the two end portions of the first lighting module 40b are electrically connected to the node N5_b and the node N6_b, respectively. There is a voltage difference between the node N5_b and the node N6_b, and this voltage difference is substantially equal to the sum of the power supply voltage Vdc_b and the first modulation voltage Vo_1b, and the first driving the first lighting module 40b. It acts as a driving voltage VLED_1b. Both the power supply voltage Vdc_b generated by the first power conversion module 21b and the second modulation voltage Vo_2b generated by the third power conversion module 25b are supplied to the second lighting module 60b to be supplied to the second lighting module 60b. Drive. The second modulation voltage Vo_2b is adjusted so as to change the illumination intensity of the second illumination module 60b. Two ends of the second lighting module 60b are electrically connected to the node N5_b and the node N7_b, respectively. There is a voltage difference between the node N5_b and the node N7_b, and this voltage difference is substantially equal to the sum of the power supply voltage Vdc_b and the second modulation voltage Vo_2b, and the second driving the second lighting module 60b. It acts as a driving voltage VLED_2b. The power supply voltage Vdc_b generated by the first power conversion module 21b is lower than the cut-in voltage Vf_1b of the first lighting module 40b and the cut-in voltage Vf_2b of the second lighting module 60b.

  In one embodiment of the present invention, the first control unit 2114b in the first power conversion module 21b adjusts the potential of the power supply voltage Vdc_b according to the feedback signal SF_b. The adjustment of the potential of the power supply voltage Vdc_b in accordance with the feedback signal SF_b can be referred to as the related operation in FIG.

  In one embodiment of the present invention, the second control unit 233b adjusts the potential of the first modulation voltage Vo_1b according to the first control signal SC_1b and the first feedback signal SR_1b. The first feedback signal SR_1b is obtained by directly detecting the potential of the first drive voltage VLED_1b for the first lighting module 40b, and acts to adjust the potential of the first modulation voltage Vo_1b.

  The second control unit 253b adjusts the potential of the second modulation voltage Vo_2b according to the second control signal SC_2b and the second feedback signal SR_2b. The second feedback signal SR_2b is obtained by directly detecting the potential of the second drive voltage VLED_2b for the second illumination module 60b, and acts to adjust the potential of the second modulation voltage Vo_2b.

  In summary, the present disclosure employs a first drive voltage. The first drive voltage is substantially equal to the sum of the power supply voltage and the first modulation voltage that drives the first lighting module. The first drive voltage approaches the cut-in voltage of the first lighting module by the power supply voltage. Therefore, the potential of the first drive voltage becomes higher than the potential of the cut-in voltage of the first lighting module in response to a small portion of the modulation level of the first modulation voltage, and a large portion of the modulation level. In response to changing the illumination intensity of the first illumination module. In this way, the number of modulation levels for adjusting the illumination intensity of the first illumination module is increased, and the light modulation resolution of the first illumination module is improved. Furthermore, the amount of electricity converted by the second power conversion module is reduced, and as a result, power consumption during power conversion is reduced. Therefore, the overall performance of the power adjustment circuit of the present disclosure can be improved.

Claims (11)

A power adjustment circuit for generating at least a first drive voltage for driving the first lighting module,
A first power conversion module that generates a power supply voltage and a second converted power in response to the first converted power;
A second power conversion module electrically connected to the first power conversion module, wherein a part of the second converted power is converted into a first modulation voltage, and the first modulation voltage is output. A second power conversion module that adjusts the potential of the first modulation voltage in accordance with a first control signal;
Including
The power adjustment circuit, wherein the first drive voltage is a sum of the power supply voltage and the first modulation voltage, and the power supply voltage is lower than a cut-in voltage of the first lighting module.   The first power conversion module includes an AC-DC converter and a capacitor, the AC-DC converter includes a first output end and a second output end, and two ends of the capacitor are respectively connected to the AC -Electrically connected to the first output terminal and the second output terminal of the DC converter, and the second power conversion module is electrically connected to the first output terminal of the AC-DC converter. The power adjustment circuit according to claim 1, connected to the power supply circuit.   The power adjustment circuit according to claim 2, wherein the AC-DC converter adjusts the power supply voltage in response to a first feedback signal, and the first feedback signal is related to a voltage output from a capacitor.   A third power conversion module electrically connected to the first output terminal of the AC-DC converter, wherein the other part of the second converted power is converted into a second modulation voltage; The power converter module further includes a third power conversion module that outputs the second modulation voltage when the AC-DC converter outputs the other portion of the second converted power to the third power conversion module. 2. The power adjustment circuit according to 2.   The third power conversion module adjusts the potential of the second modulation voltage in response to a second control signal, and the sum of the power supply voltage and the second modulation voltage drives the second illumination module. The power adjustment circuit according to claim 4, wherein the power adjustment circuit is a second drive voltage.   The upper limit of the first drive voltage is related to a rated voltage of the first lighting module, and the upper limit of the second drive voltage is related to a rated voltage of the second lighting module. 5. The power adjustment circuit according to 5.   The power adjustment circuit according to claim 5, wherein the power supply voltage is lower than a cut-in voltage of the first lighting module and a cut-in voltage of the second lighting module.   The power according to claim 5, wherein a sum of an output power value of the second power conversion module and an output power value of the third power conversion module is substantially equal to a power value of the second converted power. Adjustment circuit.   The power adjustment according to claim 5, wherein a maximum converted power value of the second power conversion module or a maximum converted power value of the third power conversion module is substantially equal to a power value of the second converted power. circuit.   The second power conversion module adjusts the first modulation voltage in response to a second feedback signal and the first control signal, and the second feedback signal is related to the first modulation voltage. The power adjustment circuit according to claim 1.   The power adjustment circuit according to claim 1, wherein the power supply voltage is a constant voltage.

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