Power supply control circuit, power supply control method, and LED driving circuit

Abstract

The application provides a power supply control circuit, a power supply control method and an LED driving circuit. The power supply control circuit comprises a first voltage conversion circuit, a power supply voltage control circuit, a driving voltage control circuit and a switch control circuit. The first voltage conversion circuit is used for converting a first voltage into a power supply voltage. The input end of the power supply voltage control circuit is coupled with the first voltage conversion circuit, and the power supply voltage control circuit is used for outputting a first control signal according to the power supply voltage. The input end of the driving voltage control circuit receives a characteristic signal representing a driving voltage, and the driving voltage control circuit is used for outputting a second control signal according to the characteristic signal. The switch control circuit is used for generating a switch driving signal according to the first control signal and the second control signal. The power supply control circuit, the power supply control method and the LED driving circuit provided by the application can solve the power supply and driving voltage control problems of a multi-channel LED driving circuit, simplify the system power supply architecture and effectively save the system cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of power electronics, and relates to an LED driving technology, in particular to a power supply control circuit, a power supply control method and an LED driving circuit. BACKGROUND

[0002] LED lamps are widely used in the lighting field due to their high brightness, low power consumption and long service life. In the LED driving circuit, the existing LED driving module and the auxiliary power supply module are separated, the LED current is controlled by the LED driving module, and the dimming module is powered by the auxiliary power supply module, which requires two sets of circuits and control chips to realize, and the peripheral circuit is relatively complex. With the continuous improvement of the demand for lighting quality, RGB+W lamp strings and RGB+CW lamp strings and other lighting schemes have gradually appeared. When it comes to RGB+CW 5-way LED driving circuits, if the lamp string voltage difference of the RGB lamp string and the CW lamp string is relatively large, the same power supply voltage cannot be used to realize the power supply of the RGB lamp string and the CW lamp string, so an additional power supply module is needed to power the RGB lamp string, making the system more complex and the production cost higher.

[0003] Therefore, it is necessary to provide a new structure or control method to solve at least part of the above problems. SUMMARY

[0004] In view of one or more problems in the prior art, the present application provides a power supply control circuit, a power supply control method and an LED driving circuit.

[0005] According to one aspect of the present application, a power supply control circuit is disclosed, which comprises:

[0006] a first voltage conversion circuit for converting a first voltage into a power supply voltage to power the power supply control circuit;

[0007] a power supply voltage control circuit, the input end of which is coupled to the first voltage conversion circuit, for outputting a first control signal according to the power supply voltage to control the power supply voltage;

[0008] a driving voltage control circuit, the input end of which receives a representation signal representing the driving voltage, for outputting a second control signal according to the representation signal to control the driving voltage; the power supply voltage or the driving voltage is used to drive a first load, and the driving voltage is used to drive a second load; and

[0009] a switch control circuit, the first input end of which is coupled to the power supply voltage control circuit, and the second input end of which is coupled to the driving voltage control circuit, for generating a switch driving signal according to the first control signal and the second control signal to control a main switch tube.

[0010] Preferably, the power supply voltage control circuit comprises a first comparison circuit, a first input terminal of which is coupled to the first reference signal terminal to receive the first reference signal, a second input terminal of which is coupled to the power supply voltage terminal to receive the power supply voltage, and an output terminal of which outputs a first control signal.

[0011] Preferably, the characteristic signal is an analog signal, and the drive voltage control circuit comprises:

[0012] an operational amplifier circuit, a first input terminal of which is coupled to the second reference signal terminal to receive the second reference signal, and a second input terminal of which is coupled to the characteristic signal terminal to receive the characteristic signal; and

[0013] a first capacitor, a first terminal of which is coupled to the output terminal of the operational amplifier circuit and the switch control circuit respectively, and a second terminal of which is coupled to the reference ground.

[0014] Preferably, the characteristic signal is a logic signal, and the drive voltage control circuit comprises:

[0015] a first capacitor, a first terminal of which is coupled to the switch control circuit, and a second terminal of which is coupled to the reference ground; and

[0016] a charge-discharge control circuit, an input terminal of which is coupled to the characteristic signal terminal to receive the characteristic signal, for controlling the charge-discharge of the first capacitor according to the characteristic signal.

[0017] Preferably, the switch control circuit comprises:

[0018] a conduction time control circuit, a first input terminal of which is coupled to the power supply voltage control circuit, and a second input terminal of which is coupled to the drive voltage control circuit, for controlling the conduction time of the main switch according to the first control signal and the second control signal; and

[0019] a switch drive signal generation circuit, an input terminal of which is coupled to the output terminal of the conduction time control circuit, and an output terminal of which is coupled to the main switch, for outputting a switch drive signal.

[0020] Preferably, the first voltage conversion circuit comprises an auxiliary winding, and the first voltage is converted into the power supply voltage by the first voltage conversion circuit.

[0021] Preferably, the power supply control circuit further comprises a second voltage conversion circuit, an input terminal of which is coupled to the power supply voltage terminal to receive the power supply voltage, for converting the power supply voltage into a second voltage to supply power to the communication module.

[0022] According to another aspect of the present application, there is disclosed an LED driving circuit, the LED driving circuit comprising a drive voltage conversion circuit and the power supply control circuit as claimed in any one of the preceding claims, and the drive voltage outputted by the drive voltage conversion circuit is controlled by controlling the switching state of the main switch.

[0023] Preferably, the power supply voltage control circuit is configured to control the driving voltage conversion circuit to operate in a high power output mode when the power supply voltage is lower than a third reference signal, so as to increase the output energy of the driving voltage conversion circuit.

[0024] Preferably, the power supply voltage is used to drive a first load, and the driving voltage is used to drive a second load; the first load is an RGB light string, and the second load is a cool white light string and a warm white light string.

[0025] Preferably, the driving voltage is used to drive a first load and a second load; the first load is an RGB light string, and the second load is a cool white light string and a warm white light string.

[0026] According to yet another aspect of the present application, a power supply control method is disclosed, the power supply control method comprising:

[0027] converting the first voltage into a power supply voltage to power a power supply control circuit;

[0028] outputting a first control signal according to the power supply voltage to control the power supply voltage;

[0029] outputting a second control signal according to a characteristic signal representing the driving voltage to control the driving voltage; wherein the power supply voltage is used to drive a first load, and the driving voltage is used to drive a second load; and

[0030] generating a switch driving signal according to the first control signal and the second control signal to control a main switch tube.

[0031] Preferably, the step of outputting the first control signal according to the power supply voltage comprises comparing a first reference signal and the power supply voltage to generate the first control signal.

[0032] Preferably, the step of outputting the second control signal according to the characteristic signal representing the driving voltage comprises:

[0033] generating the second control signal according to a second reference signal and the characteristic signal, the characteristic signal being an analog signal; or

[0034] controlling the charging and discharging of a first capacitor according to the characteristic signal, and obtaining the second control signal through a first terminal of the first capacitor, the characteristic signal being a logic signal.

[0035] Preferably, the power supply control method further comprises converting the power supply voltage into a second voltage to power a communication module.

[0036] Preferably, the power supply control method further comprises controlling the driving voltage conversion circuit to operate in a high power output mode when the power supply voltage is lower than a third reference signal, so as to increase the output energy of the driving voltage conversion circuit.

[0037] Preferably, the supply voltage is used to drive the first load, and the driving voltage is used to drive the second load, the first load is an RGB light string, and the second load is a cool white light string and a warm white light string.

[0038] Preferably, the driving voltage is used to drive the first load and the second load, the first load is an RGB light string, and the second load is a cool white light string and a warm white light string.

[0039] The application provides a supply control circuit, a supply control method and an LED driving circuit. The supply control circuit comprises a first voltage conversion circuit, a supply voltage control circuit, a driving voltage control circuit and a switch control circuit. The first voltage conversion circuit is used to convert a first voltage into a supply voltage to supply power to the supply control circuit. An input end of the supply voltage control circuit is coupled to the first voltage conversion circuit, and the supply voltage control circuit is used to output a first control signal according to the supply voltage to control the supply voltage. An input end of the driving voltage control circuit receives a characteristic signal representing a driving voltage, and the driving voltage control circuit is used to output a second control signal according to the characteristic signal to control the driving voltage. The supply voltage or the driving voltage is used to drive a first load, and the driving voltage is used to drive a second load. A first input end of the switch control circuit is coupled to the supply voltage control circuit, a second input end of the switch control circuit is coupled to the driving voltage control circuit, and the switch control circuit is used to generate a switch driving signal according to the first control signal and the second control signal to control a main switch tube. The supply control circuit, the supply control method and the LED driving circuit provided by the application can solve the problem of supply and driving voltage control of a multi-channel LED driving circuit, simplify the system power architecture and effectively save the system cost. BRIEF DESCRIPTION OF DRAWINGS

[0040] The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and are not intended to limit the application. In the drawings:

[0041] Figure 1 FIG. 1 shows a circuit structure schematic diagram of a supply control circuit according to an embodiment of the application;

[0042] Figure 2 FIG. 3 shows a circuit structure schematic diagram of a supply control circuit according to another embodiment of the application;

[0043] Figure 3 FIG. 5 shows a circuit structure schematic diagram of an LED driving circuit according to an embodiment of the application;

[0044] Figure 4 FIG. 7 shows a step schematic diagram of a supply control method according to an embodiment of the application. DETAILED DESCRIPTION

[0045] For further understanding of the present application, preferred embodiments thereof will be described in detail below with reference to the following examples, but it should be understood that the description is only further explanation of the features and advantages of the present application, and is not a limitation on the claims of the present application.

[0046] The description of this part is only for several typical embodiments, and the present application is not limited to the scope described in the embodiments. The combination of different embodiments, the mutual replacement of some technical features in different embodiments, and the mutual replacement of some technical features in the embodiments and the same or similar prior art means are within the description and protection scope of the present application.

[0047] In the specification, "coupling" or "connection" includes both direct connection and indirect connection. Indirect connection is the connection through an intermediate medium, such as the connection through an electrically conductive medium such as a conductor, which can contain parasitic inductance or parasitic capacitance, or through the intermediate circuit or component described in the embodiments of the specification; indirect connection can also include the connection through other active devices or passive devices on the basis of achieving the same or similar functions, such as the connection through circuits or components such as switches, signal amplification circuits, follower circuits, etc. "Multiple" or "many" means two or more. In addition, in the present application, words such as first, second, etc. are mainly used to distinguish one technical feature from another technical feature, and do not necessarily require or imply a certain actual relationship or order between the technical features.

[0048] An embodiment of the present application discloses a power supply control circuit, which comprises a first voltage conversion circuit, a power supply voltage control circuit, a driving voltage control circuit and a switch control circuit. The first voltage conversion circuit is used to convert a first voltage into a power supply voltage to supply power to the power supply control circuit. The input end of the power supply voltage control circuit is coupled to the first voltage conversion circuit, and the power supply voltage control circuit is used to output a first control signal according to the power supply voltage to control the power supply voltage. The input end of the driving voltage control circuit receives a characteristic signal representing a driving voltage, and the driving voltage control circuit is used to output a second control signal according to the characteristic signal to control the driving voltage. The power supply voltage or the driving voltage is used to drive a first load, and the driving voltage is used to drive a second load. The first input end of the switch control circuit is coupled to the power supply voltage control circuit, and the second input end of the switch control circuit is coupled to the driving voltage control circuit, and the switch control circuit is used to generate a switch driving signal according to the first control signal and the second control signal to control a main switch tube. In an embodiment, the characteristic signal representing the driving voltage is an analog signal. In another embodiment, the characteristic signal representing the driving voltage is a logic signal.

[0049] In an embodiment of the present application, as Figure 1As shown, the power supply control circuit includes a first voltage conversion circuit 10, a power supply voltage control circuit 11, a driving voltage control circuit 12 and a switch control circuit 13. The driving voltage conversion circuit 14 is coupled to the input voltage Vin, and the driving voltage Vbus can be obtained through the driving voltage conversion circuit 14. In addition, the first voltage can also be obtained through the driving voltage conversion circuit 14, and the first voltage can be controlled through the control of the main switch tube. Preferably, the driving voltage conversion circuit includes a rectifier circuit and a switching conversion circuit, the rectifier circuit is used to convert the alternating input voltage Vin into a direct current signal, and the switching conversion circuit is used to convert the direct current signal into the driving voltage Vbus. As shown in the figure, Figure 1 As shown, the input end of the power supply voltage control circuit 11 is coupled to the first voltage conversion circuit 10, and the first voltage conversion circuit 10 is used to convert the first voltage into the power supply voltage VDD, which is used to supply power to the power supply control circuit. The power supply voltage control circuit 11 is used to output the first control signal according to the power supply voltage VDD, and the first control signal is used to control the adjustment of the power supply voltage VDD. The input end of the driving voltage control circuit 12 receives the characteristic signal representing the driving voltage Vbus, and the driving voltage control circuit 12 is used to output the second control signal according to the characteristic signal, and the second control signal is used to control the adjustment of the driving voltage Vbus. Wherein, the power supply voltage VDD or the driving voltage Vbus is used to drive the first load, and the driving voltage Vbus is used to drive the second load. The first input end of the switch control circuit 13 is coupled to the output end of the power supply voltage control circuit 11, and the second input end of the switch control circuit 13 is coupled to the output end of the driving voltage control circuit 12, and the switch control circuit 13 is used to generate the switch driving signal according to the first control signal and the second control signal, and the switch driving signal is used to control the switching state of the main switch tube Q1.

[0050] In an embodiment of the present application, the driving voltage conversion circuit can be one of the topological circuits such as the step-down switching circuit, the step-up switching circuit, the step-up / step-down switching circuit and the flyback switching circuit. In an embodiment of the present application, the main switch tube Q1 is arranged in the power supply control circuit. In another embodiment of the present application, the main switch tube Q1 is arranged in the driving voltage conversion circuit 14, and the main switch tube Q1 can be arranged according to specific needs. In a specific embodiment, the main switch tube can be one of the metal oxide semiconductor field effect transistor (MOSFET), the junction field effect transistor (JFET) and the insulated gate bipolar transistor (IGBT).

[0051] In another embodiment of the present application, as shown in the figure, Figure 2As shown, the power supply control circuit includes a first voltage conversion circuit (not shown), a power supply voltage control circuit, a driving voltage control circuit and a switch control circuit 23. In a preferred embodiment, the power supply voltage control circuit includes a first comparison circuit 21, a first input terminal of the first comparison circuit 21 is coupled to a first reference signal terminal to receive a first reference signal Vrefl, a second input terminal of the first comparison circuit 21 is coupled to a power supply voltage terminal to receive a power supply voltage VDD, and an output terminal of the first comparison circuit 21 outputs a first control signal. In a preferred embodiment, the driving voltage control circuit includes an operational amplifier circuit 22 and a first capacitor Cl, a first input terminal of the operational amplifier circuit 22 is coupled to a second reference signal terminal to receive a second reference signal Vref2, a second input terminal of the operational amplifier circuit 22 is coupled to a characteristic signal terminal to receive a characteristic signal Vl_fb, which is used to represent the driving voltage. A first terminal of the first capacitor Cl is coupled to an output terminal of the operational amplifier circuit 22 and the switch control circuit 23, respectively, and a second terminal of the first capacitor Cl is coupled to a reference ground. In a preferred embodiment, the switch control circuit 23 includes a conduction time control circuit 231 and a switch driving signal generation circuit 232. A first input terminal of the conduction time control circuit 231 is coupled to the power supply voltage control circuit, a second input terminal of the conduction time control circuit 231 is coupled to the driving voltage control circuit, and the conduction time control circuit 231 controls the conduction time of the main switch Ql according to the first control signal and the second control signal, and controls the switching state of the main switch Ql by controlling the conduction time of the main switch Ql, thereby controlling the power supply voltage VDD and the driving voltage Vbus, respectively. An input terminal of the switch driving signal generation circuit 232 is coupled to an output terminal of the conduction time control circuit 231, and an output terminal of the switch driving signal generation circuit 232 is coupled to a control terminal of the main switch Ql, and the switch driving signal generation circuit 232 is used to output a switch driving signal to drive the main switch Ql.

[0052] In a preferred embodiment of the present application, the driving voltage control circuit comprises a first capacitor and a charge-discharge control circuit. A first end of the first capacitor is coupled to the switch control circuit, and a second end of the first capacitor is coupled to a reference ground. An input end of the charge-discharge control circuit is coupled to the characteristic signal end LFB to receive a characteristic signal, which is a logic signal in this embodiment. The charge-discharge control circuit is configured to control the charging and discharging of the first capacitor according to the characteristic signal, and the logic signal is used to control the driving voltage. The logic signal can be obtained according to the driving voltage and a reference signal. When the driving voltage is less than the reference signal, the logic signal is at a first logic level; when the driving voltage is greater than the reference signal, the logic signal is at a second logic level. For example, when the logic signal is at the first logic level (e.g., high level), the charge-discharge control circuit controls the charging of the first capacitor; when the logic signal is at the second logic level (e.g., low level), the charge-discharge control circuit controls the discharging of the first capacitor. The first end of the first capacitor outputs a second control signal, and the switch control circuit controls the switching state of the switch tube according to the second control signal, thereby achieving the control of the driving voltage.

[0053] An embodiment of the present application discloses an LED driving circuit, which comprises a driving voltage conversion circuit and the power supply control circuit as described in any of the above embodiments. The switching state of the main switch tube is controlled to control the driving voltage output by the driving voltage conversion circuit. In an embodiment of the present application, as shown in Figure 3 , the LED driving circuit comprises a driving voltage conversion circuit, a power supply control circuit and a load. The driving circuit conversion circuit comprises a rectifier circuit and a switching conversion circuit, and the rectifier circuit is a rectifier bridge circuit. In an embodiment as shown in Figure 3 , the switching conversion circuit is a boost-type switching circuit, and of course, a suitable topology circuit can be selected according to the actual circuit needs. The boost-type switching circuit comprises a first inductor L1, a first diode D1, a main switch tube Q1 (not shown in the figure) and a second capacitor C2. A first end of the first inductor L1 is coupled to the rectifier circuit, an anode of the first diode D1 is coupled to a second end of the first inductor L1, a first end of the second capacitor C2 is coupled to a cathode of the first diode D1, and a second end of the second capacitor C2 is coupled to the ground. The power supply control circuit comprises a first chip, and the main switch tube Q1 is arranged in the first chip. The first chip is provided with a drain pin, a current sampling pin and a power supply voltage end pin. Preferably, the main switch tube is a field effect transistor, the drain of the main switch tube Q1 is coupled to the drain pin of the first chip, and the source of the main switch tube Q1 is coupled to the current sampling pin. The power supply control circuit comprises a first voltage conversion circuit, a power supply voltage control circuit, a driving voltage control circuit and a switch control circuit.

[0054] Preferably, in an embodiment, the first voltage conversion circuit comprises an auxiliary winding L2, the first voltage conversion circuit is configured to convert the first voltage into a supply voltage, and output the supply voltage to the supply voltage terminal pin. Specifically, the first voltage can be obtained from the driving voltage conversion circuit. The supply voltage control circuit outputs a first control signal to control the supply voltage according to the supply voltage, and the driving voltage control circuit outputs a second control signal to control the driving voltage according to the characteristic signal representing the driving voltage. The switch control circuit generates a switch driving signal according to the first control signal and the second control signal, and the switch driving signal is used to control the switching state of the main switch tube. By controlling the switching state of the main switch tube, the driving voltage Vbus output by the driving voltage conversion circuit can be controlled. In the embodiment as shown in Figure 3 the load comprises an RGB lamp string, a cool white lamp string, and a warm white lamp string. The supply voltage VDD is used to power the supply control circuit, and in addition, the supply voltage VDD is also used to drive the RGB lamp string. The driving voltage Vbus is used to drive the cool white lamp string and the warm white lamp string.

[0055] In a preferred embodiment, as shown in Figure 3 the LED driving circuit further comprises a dimming module, the dimming module is configured to perform dimming control on the RGB lamp string, the cool white lamp string, and the warm white lamp string according to a control signal obtained from the communication module. The communication module can be one of a Bluetooth module, a Zigbee module, and a Wifi module. In the embodiment as shown in Figure 3 the communication module sends an I2C signal to the dimming module, and the dimming module performs dimming control on the RGB lamp string, the cool white lamp string, and the warm white lamp string according to the I2C signal. Preferably, the dimming module can be powered by the supply voltage VDD or the driving voltage Vbus. Preferably, the supply control circuit further comprises a second voltage conversion circuit, an input terminal of the second voltage conversion circuit is coupled to the supply voltage terminal to receive the supply voltage, and the second voltage conversion circuit is configured to convert the supply voltage into a second voltage to power the communication module.

[0056] In an embodiment of the present application, the supply voltage control circuit is configured to control the driving voltage conversion circuit to work in a power increasing output mode when the supply voltage is lower than a third reference signal, the power increasing output mode comprises a peak value control mode or charging a control loop of the driving voltage conversion circuit, and the power increasing output mode can also comprise the peak value control mode and charging the control loop of the driving voltage conversion circuit. Controlling the driving voltage conversion circuit to work in the power increasing output mode is configured to increase the output energy of the driving voltage conversion circuit, so as to increase the supply voltage value. The peak value control mode specifically refers to controlling the current flowing through the first inductor or the current flowing through the main switch tube to be a peak current value in this mode.

[0057] In an embodiment of the present application, the supply voltage is used to drive a first load, and the driving voltage is used to drive a second load. The first load is a RGB light string, and the second load is a cool white light string and a warm white light string.

[0058] In another embodiment of the present application, the driving voltage is used to drive the first load and the second load. The first load is a RGB light string, and the second load is a cool white light string and a warm white light string.

[0059] An embodiment of the present application further discloses a supply control method, as shown in Figure 4 The supply control method comprises:

[0060] Step S100, converting the first voltage into a supply voltage to power a supply control circuit;

[0061] Step S200, outputting a first control signal according to the supply voltage to control the supply voltage;

[0062] Step S300, outputting a second control signal according to a characteristic signal representing the driving voltage to control the driving voltage; wherein the supply voltage or the driving voltage is used to drive a first load, and the driving voltage is used to drive a second load; and

[0063] Step S400, generating a switch driving signal according to the first control signal and the second control signal to control a main switch tube.

[0064] In a preferred embodiment of the present application, the step of outputting the first control signal according to the supply voltage comprises comparing a first reference signal with the supply voltage to generate the first control signal.

[0065] In a preferred embodiment of the present application, the step of outputting the second control signal according to the characteristic signal representing the driving voltage comprises generating the second control signal according to a second reference signal and the characteristic signal, the characteristic signal being an analog signal. In another embodiment, the step of outputting the second control signal according to the characteristic signal representing the driving voltage comprises controlling the charge and discharge of a first capacitor according to the characteristic signal, obtaining the second control signal through a first terminal of the first capacitor, the characteristic signal being a logic signal, and a second terminal of the first capacitor being coupled to a ground.

[0066] In a preferred embodiment of the present application, the supply control method further comprises converting the supply voltage into a second voltage to power a communication module.

[0067] In a preferred embodiment of the present application, the power supply control method further comprises: controlling the driving voltage conversion circuit to work in a power output increasing mode when the power supply voltage is lower than the third reference signal, the power output increasing mode comprising a fixed peak value mode or a mode of charging the control loop of the driving voltage conversion circuit, the power output increasing mode can also comprise the fixed peak value mode and the mode of charging the control loop of the driving voltage conversion circuit, and the driving voltage conversion circuit working in the power output increasing mode is used to increase the output energy of the driving voltage conversion circuit.

[0068] In a preferred embodiment of the present application, the power supply voltage is used to drive the first load, and the driving voltage is used to drive the second load, the first load being an RGB lamp string, and the second load being a cool white lamp string and a warm white lamp string.

[0069] In a preferred embodiment of the present application, the driving voltage is used to drive the first load and the second load, the first load being an RGB lamp string, and the second load being a cool white lamp string and a warm white lamp string.

[0070] The present application provides a power supply control circuit, a power supply control method and an LED driving circuit. The power supply control circuit comprises a first voltage conversion circuit, a power supply voltage control circuit, a driving voltage control circuit and a switch control circuit. The first voltage conversion circuit is used to convert a first voltage into a power supply voltage to supply power to the power supply control circuit. The input end of the power supply voltage control circuit is coupled to the first voltage conversion circuit, and the power supply voltage control circuit is used to output a first control signal according to the power supply voltage to control the power supply voltage. The input end of the driving voltage control circuit receives a characteristic signal representing the driving voltage, and the driving voltage control circuit is used to output a second control signal according to the characteristic signal to control the driving voltage. The power supply voltage or the driving voltage is used to drive the first load, and the driving voltage is used to drive the second load. The first input end of the switch control circuit is coupled to the power supply voltage control circuit, and the second input end of the switch control circuit is coupled to the driving voltage control circuit. The switch control circuit is used to generate a switch driving signal according to the first control signal and the second control signal to control a main switch tube. The power supply control circuit, the power supply control method and the LED driving circuit provided by the present application can solve the power supply and driving voltage control problems of the multi-channel LED driving circuit, simplify the system power architecture and effectively save the system cost.

[0071] Those skilled in the art should know that the "high level" and "low level", "set" and "reset", "and gate" and "or gate", "in-phase input end" and "inverted input end" and other logic controls in the description or drawings can be exchanged or changed, and the same functions or purposes as the above embodiments can be realized by adjusting the subsequent logic controls.

[0072] The description and applications of the present application are illustrative, and not intended to limit the scope of the present application. The related descriptions of effects or advantages etc. involved in the specification are not intended to limit the scope of the present application, and are only intended to describe the related descriptions of effects or advantages etc. in the specification. Variations and changes may be made to the disclosed embodiments, and it is intended that the application encompass variations and modifications. It is intended that the application not be limited to the embodiments disclosed in the specification, but include all embodiments that would normally occur to one of ordinary skill in the art. It is intended that the application not be limited to the disclosed embodiments, but include all embodiments that would normally occur to one of ordinary skill in the art. The person skilled in the art should understand that the present application can be implemented in other forms, structures, arrangements, proportions, and with other components, materials and parts without departing from the spirit or essential characteristics of the present application. Other variations and changes may be made to the disclosed embodiments without departing from the scope and spirit of the application.

Claims

1. A power supply control circuit, characterized by comprising: The power supply control circuit comprises: a first voltage conversion circuit comprising an auxiliary winding, configured to convert the first voltage into a power supply voltage to supply power to the power supply control circuit; a power supply voltage control circuit, an input end of which is coupled to the first voltage conversion circuit, configured to output a first control signal according to the power supply voltage to control the power supply voltage; the power supply voltage control circuit comprises a first comparison circuit, a first input end of the first comparison circuit is coupled to a first reference signal end to receive a first reference signal, a second input end of the first comparison circuit is coupled to a power supply voltage end to receive the power supply voltage, and an output end of the first comparison circuit outputs the first control signal; a drive voltage control circuit, an input end of which receives a characteristic signal representing the drive voltage, configured to output a second control signal according to the characteristic signal to control the drive voltage; the power supply voltage or the drive voltage is used to drive a first load, and the drive voltage is used to drive a second load; and a switch control circuit, a first input end of which is coupled to the power supply voltage control circuit, and a second input end of which is coupled to the drive voltage control circuit, configured to generate a switch driving signal according to the first control signal and the second control signal to control a main switch tube.

2. The power supply control circuit of claim 1, wherein, The characteristic signal is an analog signal, and the drive voltage control circuit comprises: an operational amplifier circuit, a first input end of which is coupled to a second reference signal end to receive a second reference signal, and a second input end of which is coupled to a characteristic signal end to receive the characteristic signal; and a first capacitor, a first end of which is coupled to an output end of the operational amplifier circuit and the switch control circuit respectively, and a second end of which is coupled to a reference ground.

3. The power supply control circuit of claim 1, wherein, The characteristic signal is a logic signal, and the drive voltage control circuit comprises: a first capacitor, a first end of which is coupled to the switch control circuit, and a second end of which is coupled to the reference ground; and a charge-discharge control circuit, an input end of which is coupled to a characteristic signal end to receive the characteristic signal, configured to control the charge-discharge of the first capacitor according to the characteristic signal.

4. The power supply control circuit of claim 1, wherein, The switch control circuit comprises: a conduction time control circuit, a first input end of which is coupled to the power supply voltage control circuit, and a second input end of which is coupled to the drive voltage control circuit, configured to control the conduction time of the main switch tube according to the first control signal and the second control signal; and a switch driving signal generation circuit, an input end of which is coupled to an output end of the conduction time control circuit, and an output end of which is used to be coupled to the main switch tube, configured to output the switch driving signal.

5. The power supply control circuit of claim 1, wherein, The power supply control circuit further comprises: a second voltage conversion circuit, an input end of which is coupled to a power supply voltage end to receive the power supply voltage, configured to convert the power supply voltage into a second voltage to supply power to a communication module.

6. An LED driving circuit, characterized by comprising: The LED driving circuit comprises a drive voltage conversion circuit and the power supply control circuit according to any one of claims 1-5, and the switch state of the main switch tube is controlled to control the drive voltage output by the drive voltage conversion circuit.

7. The LED driving circuit of claim 6, wherein, The power supply voltage control circuit is used to control the drive voltage conversion circuit to work in a power output increasing mode when the power supply voltage is lower than a third reference signal, so as to increase the output energy of the drive voltage conversion circuit.

8. The LED driving circuit of claim 6, wherein, The power supply voltage is used to drive a first load, and the drive voltage is used to drive a second load; the first load is an RGB lamp string, and the second load is a cool white lamp string and a warm white lamp string.

9. The LED driving circuit of claim 6, wherein, The driving voltage is used to drive the first load and the second load; the first load is an RGB lamp string, and the second load is a cool white lamp string and a warm white lamp string.

10. A power supply control method characterized by, The power supply control method comprises: The first voltage is converted into a power supply voltage to supply power to the power supply control circuit; The first control signal is output according to the power supply voltage to control the power supply voltage; the step of outputting the first control signal according to the power supply voltage comprises: comparing the first reference signal with the power supply voltage to generate the first control signal; The second control signal is output according to the characteristic signal representing the driving voltage to control the driving voltage; wherein the power supply voltage or the driving voltage is used to drive the first load, and the driving voltage is used to drive the second load; and The switching driving signal is generated according to the first control signal and the second control signal to control the main switch tube.

11. The power supply control method according to claim 10, wherein The step of outputting the second control signal according to the characteristic signal representing the driving voltage comprises: The second control signal is generated according to the second reference signal and the characteristic signal, and the characteristic signal is an analog signal; or The charging and discharging of the first capacitor is controlled according to the characteristic signal, the second control signal is obtained through the first end of the first capacitor, and the characteristic signal is a logic signal.

12. The power supply control method of claim 10, wherein, The power supply control method further comprises: converting the power supply voltage into a second voltage to supply power to the communication module.

13. The power supply control method of claim 10, wherein, The power supply control method further comprises: when the power supply voltage is lower than a third reference signal, controlling the driving voltage conversion circuit to work in a power output increasing mode to increase the output energy of the driving voltage conversion circuit.

14. The power supply control method of claim 10, wherein, The power supply voltage is used to drive the first load, and the driving voltage is used to drive the second load; the first load is an RGB lamp string, and the second load is a cool white lamp string and a warm white lamp string.

15. The power supply control method of claim 10, wherein, The driving voltage is used to drive the first load and the second load; the first load is an RGB lamp string, and the second load is a cool white lamp string and a warm white lamp string.

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