WO2022082890A1

WO2022082890A1 - Alternating-current and direct-current switching lighting drive circuit and lamp

Info

Publication number: WO2022082890A1
Application number: PCT/CN2020/127920
Authority: WO
Inventors: 李胜森; 罗杨洋; 杨林; 杨海涛
Original assignee: 深圳市豪恩智能物联股份有限公司
Priority date: 2020-10-22
Filing date: 2020-11-10
Publication date: 2022-04-28
Also published as: CN213368188U

Abstract

Disclosed are an alternating-current and direct-current switching lighting drive circuit and a lamp. The circuit comprises: a rectification circuit (11) for performing rectification processing on a power source voltage signal provided by an input power source circuit (01), so as to generate a rectified voltage signal; a transformation power conversion circuit (12) for performing voltage conversion processing on the rectified voltage signal, so as to generate a drive voltage signal to drive a load (100); a voltage sampling circuit (13) for performing voltage sampling on the rectified voltage signal, so as to generate a voltage sampling signal; a comparison circuit (14) for generating a power adjustment enable signal according to the voltage sampling signal being lower than a reference voltage signal; and a power control circuit (15) for generating a drive control signal according to the power adjustment enable signal, so as to adjust the drive voltage signal. When the alternating-current and direct-current switching lighting drive circuit is connected to an alternating-current power source, a drive voltage signal with a full-load power can be output, and when the alternating-current and direct-current switching lighting drive circuit is connected to an emergency direct-current power source, power consumption can be reduced, such that the alternating-current and direct-current switching lighting drive circuit can be used when being connected to different power sources, thereby prolonging the service time of the emergency direct-current power source, and meeting the design specifications and standards of an emergency lighting system.

Description

AC-DC switching lighting drive circuit and lamps

technical field

The present application relates to the technical field of lighting, and in particular to an AC-DC switching lighting drive circuit and a lamp.

Background technique

The statements herein merely provide background information related to the present application and do not necessarily constitute prior art. At present, when the traditional pure alternating current (AC) input lighting products are replaced, they are not connected to the direct current (DC) emergency system to reduce the power. The power of the entire emergency system will be consumed soon. For example, the general lighting circuit can be used in the 198-264V DC emergency system, but it can only be fully loaded, and has no power reduction function, so it does not save energy; the general lighting circuit with its own dimming function , dimming through pulse width modulation signal PWM, or dimming through external 0-10V dimming module, the dimming method cannot meet the application needs of the majority of the market, and in some application environments without 0-10V dimming control board, dimming The cost of light function is high, so that in the DC emergency system 198-264V, even if there is a dimming function, it cannot meet the lighting needs of the emergency system, because the emergency lighting system design specification standard clearly stipulates that different occasions should be designed with reference to the emergency system specification standards, such as Some applications do not allow emergency lighting circuits to set sockets, some emergency lighting is strictly forbidden to use dimming devices, and some require the workplace: the illuminance of safety lighting is not less than 5% of the general lighting illuminance in the occasion, and the illuminance value of standby lighting is divided by Unless otherwise specified, it shall not be lower than 10% of the general lighting illumination of the occasion.

Therefore, there is a problem in the traditional technical solution that the lighting circuit can be used in the DC emergency system 198-264V, but it can only be fully loaded and has no power reduction function, so it cannot meet the design specifications of the emergency lighting system.

technical problem

One of the purposes of the embodiments of the present application is to provide an AC-DC switching lighting drive circuit and a lamp, which aims to solve the problem in the traditional technical solution that the lighting circuit can be used in the DC emergency system 198-264V, but it can only be fully loaded without reducing the voltage. The power function cannot meet the design specification standard of emergency lighting system.

technical solutions

In order to solve the above-mentioned technical problems, the technical solutions adopted in the embodiments of the present application are:

In a first aspect, an AC-DC switching lighting driving circuit is provided, which is connected to a load, and the AC-DC switching lighting driving circuit includes:

an input power circuit configured to provide a power supply voltage signal;

a rectification circuit, connected to the input power supply circuit, and configured to perform rectification processing on the power supply voltage signal to generate a rectified voltage signal;

A transformer power conversion circuit, connected to the rectification circuit, is configured to perform voltage conversion processing on the rectified voltage signal to generate a driving voltage signal, and adjust the driving voltage signal according to a driving control signal; the driving voltage signal for driving the load for lighting;

a voltage sampling circuit, connected to the rectification circuit, configured to perform voltage sampling on the rectified voltage signal to generate a voltage sampling signal;

a comparison circuit, connected to the voltage sampling circuit, configured to generate a power adjustment enable signal according to the voltage sampling signal being lower than a reference voltage signal;

A power control circuit, connected to the comparison circuit and the transformer power conversion circuit, is configured to generate the drive control signal according to the power adjustment enable signal.

In one embodiment, the transformer power conversion circuit is further configured to perform voltage conversion processing on the rectified voltage signal to generate an auxiliary power supply voltage;

The AC-DC switching lighting drive circuit further includes:

A reference voltage generation circuit, connected to the transformer power conversion circuit and the comparison circuit, is configured to generate the reference voltage signal according to the auxiliary power supply voltage.

In one embodiment, the AC-DC switching lighting driving circuit further includes:

a voltage divider power supply circuit, connected to the rectifier circuit, the transformer power conversion circuit and the power control circuit, and configured to generate a first power supply voltage according to the rectified voltage signal and the auxiliary power supply voltage, to Power control circuit power supply.

In a second aspect, a lighting fixture is provided, the lighting fixture comprising the AC-DC switching lighting driving circuit according to any one of the above.

beneficial effect

The beneficial effects of the AC-DC switching lighting drive circuit and the lamp provided by the embodiments of the present application are: the power supply voltage signal is provided through the input power supply circuit; the rectification circuit rectifies the power supply voltage signal to generate the rectified voltage signal; the transformer power conversion circuit rectifies the rectification The voltage signal is subjected to voltage conversion processing to generate a driving voltage signal, and the driving voltage signal is adjusted according to the driving control signal; the driving voltage signal is used to drive the load; the voltage sampling circuit performs voltage sampling on the rectified voltage signal to generate a voltage sampling signal; The comparison circuit generates a power adjustment enable signal according to the voltage sampling signal lower than the reference voltage signal; the power control circuit generates a drive control signal according to the power adjustment enable signal; realizes that when the AC mains is connected, the output drive voltage signal is not power adjusted , so that the driving voltage signal outputting full load power supplies power to the load; when the DC power supply voltage signal provided by the lighting emergency DC power supply is connected, the driving voltage signal output to the load is adjusted to automatically detect the AC power supply voltage provided by the input power supply circuit. Signal and DC power voltage signal, and can be used normally when connected to different power supply voltage signals; at the same time, when connected to the lighting emergency DC power supply for use, the power corresponding to the driving voltage signal can be adjusted to reduce lighting power consumption, The use time of the emergency DC power supply is prolonged, and the emergency lighting system design specification standard is met, the cost is saved, and the practicability of the lighting driving power circuit is improved.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the accompanying drawings that are used in the description of the embodiments or exemplary technologies. Obviously, the drawings in the following description are only for the present application. In some embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without any creative effort.

FIG. 1 is a schematic structural diagram of an AC-DC switching lighting drive circuit provided by an embodiment of the application;

FIG. 2 is another schematic structural diagram of an AC-DC switching lighting drive circuit provided by an embodiment of the present application;

FIG. 3 is another schematic structural diagram of an AC-DC switching lighting driving circuit provided by an embodiment of the present application;

FIG. 4 is another schematic structural diagram of an AC-DC switching lighting drive circuit provided by an embodiment of the present application;

FIG. 5 is another schematic structural diagram of an AC-DC switching lighting driving circuit according to an embodiment of the present application;

FIG. 6 is an exemplary circuit schematic diagram of an AC-DC switching lighting drive circuit provided by an embodiment of the present application;

FIG. 7 is a schematic diagram illustrating the relationship between the voltage value of the power adjustment enable signal and the power percentage of the adjustment driving voltage signal.

Embodiments of the present invention

In order to make the purpose, technical solutions and advantages of the present application more clearly understood, the present application will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present application.

It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element. The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of description, rather than indicating or implying the referred device Or the elements must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be construed as a limitation to the present application, and those of ordinary skill in the art can understand the specific meanings of the above terms according to specific situations. The terms "first" and "second" are only used for the purpose of description, and should not be understood as indicating or implying relative importance or implying indicating the number of technical features. "Plurality" means two or more, unless expressly specifically limited otherwise.

In order to illustrate the technical solutions provided in the present application, the following detailed description is given in conjunction with the specific drawings and embodiments.

FIG. 1 shows a schematic structural diagram of an AC-DC switching lighting driving circuit provided by a preferred embodiment of the present application. For the convenience of description, only the parts related to this embodiment are shown, and the details are as follows:

An AC-DC switching lighting drive circuit is connected to a load 100. The AC-DC switching lighting drive circuit includes: an input power supply circuit 01, a rectifier circuit 11, a transformer power conversion circuit 12, a voltage sampling circuit 13, a comparison circuit 14 and a power control circuit 15.

The input power supply circuit 01 is configured to provide a power supply voltage signal; the rectification circuit 11 is connected to the input power supply circuit 01 and configured to rectify the power supply voltage signal to generate a rectified voltage signal; the transformer power conversion circuit 12 is connected to the rectification circuit 11 , configured to perform voltage conversion processing on the rectified voltage signal to generate a driving voltage signal, and adjust the driving voltage signal according to the driving control signal; the driving voltage signal is used to drive the load 100 to illuminate; the voltage sampling circuit 13, and the rectifying circuit 11 is connected, configured to perform voltage sampling on the rectified voltage signal to generate a voltage sampling signal; a comparison circuit 14, connected to the voltage sampling circuit 13, is configured to generate a power adjustment enable signal according to the voltage sampling signal being lower than the reference voltage signal ; The power control circuit 15, connected with the comparison circuit 14 and the transformer power conversion circuit 12, is configured to generate a drive control signal according to the power adjustment enable signal.

In a specific implementation, the load 100 is a lighting module, such as an LED light source module. The input power supply circuit 01 is used to provide a power supply voltage signal, including an AC power supply voltage signal, such as AC 198-264V; and also includes a DC power supply voltage signal, such as DC 198-264V. The rectifier circuit 11 can rectify the input AC power supply voltage signal to generate a rectified voltage signal, for example, convert a 50Hz sine wave AC power into a unidirectional pulsating DC voltage/current with a frequency of 100Hz, and rectify the AC 198-264V The voltage value range obtained after rectification is 279-373.4V; the rectification processing of the DC power supply voltage signal by the rectification circuit 11 is specifically: performing anti-reverse processing on the DC power supply voltage signal to generate a rectified voltage signal. The voltage sampling circuit 13 samples the rectified voltage signal to generate a voltage sampling signal, and indirectly implements detection and sampling of the power supply voltage signal. The comparison circuit 14 compares the voltage sampling signal with the reference voltage signal. When the input power supply circuit 01 provides the AC power supply voltage signal, the voltage sampling signal is higher than the reference voltage signal, and the comparison circuit 14 is not higher than the reference voltage signal according to the voltage sampling signal. Generate a power adjustment enable signal or generate an invalid and disabled power adjustment enable signal, such as a relatively high-level power adjustment enable signal, so that the power control circuit 15 does not output a drive control signal, and does not output a drive control signal to the transformer power conversion circuit 12 The output driving voltage signal is adjusted. At this time, the transformer power conversion circuit 12 directly performs voltage conversion processing on the rectified voltage signal to generate a driving voltage signal, and drives the load 100 to emit light to perform full-load power operation, and the luminous flux meets the lighting application requirements; when the input power supply When the DC power supply voltage signal is provided by the circuit 01, the maximum voltage value of the DC power supply voltage signal is 264V, which is less than 276 V, the corresponding voltage sampling signal is lower than the reference voltage signal, and the comparison circuit 14 is generated according to the voltage sampling signal lower than the reference voltage signal An effective power adjustment enable signal, such as a relatively low-level enable signal, controls the power control circuit 15 to generate and output a drive control signal, and controls the transformer power conversion circuit 12 to adjust the output drive voltage signal by adjusting the drive voltage signal. Corresponding power, thereby adjusting the driving power of the driving load 100. For example, the power corresponding to the output driving voltage signal is 20% of the full load power. At this time, the power generated by the transformer power conversion circuit 12 according to the emergency DC198-264V is the full load power. 20% (that is, one-fifth of the full load power) of the driving voltage signal to drive the load 100 for normal emergency lighting work.

Optionally, the reference voltage signal is a 2.5V reference voltage.

Optionally, the driving control signal is a pulse width modulation signal, that is, a PWM signal, and different power adjustments to the driving voltage signal are realized by adjusting different duty ratios of the driving control signal.

The embodiment of the present application can realize that when the AC mains (for example, AC 198-264V) is connected, the output driving voltage signal is not power adjusted, so that the driving voltage signal outputting full load power can supply power to the load; when connecting to the lighting emergency DC power supply When the provided DC power supply voltage (such as DC 198-264V), the power corresponding to the output driving voltage signal is adjusted to automatically detect the AC power supply voltage signal and the DC power supply voltage signal, and can be connected to different power supply voltage signals. The purpose of normal use; at the same time, when the emergency lighting DC power supply is connected for use, the power of the driving voltage signal can be adjusted, the lighting power consumption can be reduced, the use time of the emergency DC power supply can be prolonged, and the emergency lighting system design specification standard can be saved. The cost increases the practicability of the lighting driving power circuit.

Referring to FIG. 2 , in one embodiment, the transformer power conversion circuit 12 is further configured to perform voltage conversion processing on the rectified voltage signal to generate an auxiliary supply voltage; the AC-DC switching lighting driving circuit further includes a reference voltage generating circuit 16 .

The reference voltage generation circuit 16, connected to the transformer power conversion circuit 12 and the comparison circuit 14, is configured to generate a reference voltage signal according to the auxiliary power supply voltage.

In the specific implementation, the reference voltage signal is obtained by the reference voltage generation circuit 16 performing voltage division and voltage stabilization on the auxiliary power supply voltage, wherein the auxiliary power supply voltage is generated by the voltage conversion processing of the rectified voltage signal by the transformer power conversion circuit 12, so as to pass The internal circuit obtains a reference voltage signal, which is used as a comparison benchmark for power adjustment of the driving voltage signal, which improves the reliability and practicability of the AC-DC switching lighting driving circuit.

Referring to FIG. 3 , in one embodiment, the AC-DC switching lighting driving circuit further includes: a voltage dividing power supply circuit 17 .

The voltage dividing power supply circuit 17 is connected to the rectifier circuit 11 , the transformer power conversion circuit 12 and the power control circuit 15 , and is configured to generate a first power supply voltage according to the rectified voltage signal and the auxiliary power supply voltage to supply power to the power control circuit 15 .

In a specific implementation, the voltage dividing power supply circuit 17 divides the rectified voltage signal and the auxiliary power supply voltage to generate a first power supply voltage, and uses the first power supply voltage to supply power to the power control circuit 15 to support the normal operation of the power control circuit 15, and No additional power supply circuit is required to provide the operating voltage required by the power control circuit 15 .

In one of the embodiments, the operating voltage required by the power control circuit 15 can also be obtained from a battery power source or a power adapter or a voltage conversion chip circuit, so that the power control circuit 15 can generate a drive control signal according to the power adjustment enable signal to drive The transformer power conversion circuit 12 adjusts the power corresponding to the driving voltage signal output to the load 100, so as to reduce the power consumption of the emergency lighting DC power supply, prolong the service life of the lighting emergency power supply, and at the same time ensure compliance with the emergency lighting system design specifications.

Referring to FIG. 4 , in one embodiment, the AC-DC switching lighting driving circuit further includes: a protection circuit 18 .

The protection circuit 18 is connected to the input power supply circuit 01 and the rectification circuit 11, and is configured to perform overcurrent protection and overtemperature protection for the power supply voltage signal.

In the specific implementation, the protection circuit 18 includes protection components, such as fuses, etc., which can disconnect the connection between the input power circuit 01 and the subsequent circuit when the current of the input AC power voltage signal is too large, and protect the latter circuit and The lighting load is not protected from overcurrent, overtemperature and overvoltage, meets safety standards, and improves the safety and reliability of the AC-DC switching lighting drive circuit.

Referring to FIG. 5 , in one embodiment, the AC-DC switching lighting driving circuit further includes: an electromagnetic filter circuit 19 , a first filter circuit 20 and a second filter circuit 21 .

The electromagnetic filter circuit 19 is connected to the protection circuit 18 and the rectifier circuit 11, and is configured to perform electromagnetic interference suppression processing on the power supply voltage signal after overcurrent protection and overtemperature protection. The first filter circuit 20 is connected to the rectifier circuit 11 and the voltage sampling circuit 13, and is configured to perform filtering and noise reduction processing on the rectified voltage signal; the second filter circuit 21, connected to the transformer power conversion circuit 12 and the load 100, is configured to The driving voltage signal is filtered and noise-reduced.

In specific implementation, the electromagnetic filter circuit 19 can suppress the electromagnetic interference in the circuit, for example, the differential mode noise/interference generated in the circuit when the input power circuit 01 provides the AC voltage signal, and can suppress the power grid surge, so as to protect the Components in the circuit are protected from inrush current damage. The first filter circuit 20 can perform filtering and noise reduction processing on the rectified voltage signal, so as to output a stable and low-noise rectified voltage signal to the voltage sampling circuit 13 and the transformer power conversion circuit 12, thereby improving the voltage sampling accuracy of the voltage sampling circuit 13. , and also improve the precision and stability reliability of the voltage conversion and other processing performed by the transformer power conversion circuit 12 on the rectified voltage signal. The second filter circuit 21 performs filtering and noise reduction processing on the driving voltage signal, so as to output the driving voltage signal with low noise interference to the load 100 , so as to drive the load 100 to work stably. The embodiments of the present application effectively improve the driving stability, reliability and safety of the AC-DC switching lighting driving circuit.

In one embodiment, as shown in FIG. 6 , the electromagnetic filter circuit includes: a first inductor L1, a thirteenth resistor R13, a fourteenth resistor R14, a second inductor L2, a first variable resistor VR1, and a first Filter capacitor CX1;

The first end of the first inductor L1, the first end of the thirteenth resistor R13, and the first end of the first filter capacitor CX1 are commonly connected to the input power circuit 01, and the first inductor L1 The second end of the thirteenth resistor R13, the first end of the first variable resistor VR1 are connected to the rectifier circuit 11 in common, and the second end of the first filter capacitor CX1 , the first end of the fourteenth resistor R14 and the first end of the second inductor L2 are connected to the input power circuit 01 in common, the second end of the second inductor L2, the fourteenth resistor The second end of R14 and the second end of the first variable resistor VR1 are commonly connected to the rectifier circuit 11 .

In one embodiment, as shown in FIG. 6 , the first filter circuit 20 includes a second filter capacitor CX2 ; the first end of the second filter capacitor CX2 is connected to the first output end of the rectifier circuit 11 , the second end of the second filter capacitor CX2 is connected to the second output end of the rectifier circuit 11 .

In one embodiment, as shown in FIG. 6 , the second filter circuit 21 includes a third filter capacitor CX3 and a seventeenth resistor R17 ; the first end of the third filter capacitor CX3 is connected to the seventeenth resistor R17 . The first end of the resistor R17 is commonly connected to the first end of the load 100 , and the second end of the third filter capacitor CX3 and the second end of the seventeenth resistor R17 are commonly connected to the first end of the load 100 . two ends.

In one embodiment, as shown in FIG. 6 , the rectifier circuit 11 includes a rectifier bridge DB1; the first input end of the rectifier bridge DB1 is connected to the first output end of the input power supply circuit 01, and the rectifier The second input end of the bridge DB1 is connected to the second output end of the input power supply circuit 01 , the first output end of the rectifier circuit 11 is connected to the first end of the load 100 , and the second end of the rectifier circuit 11 is connected to the first end of the load 100 . The output terminal is grounded.

In one embodiment, as shown in FIG. 6 , the protection circuit 18 includes a fuse F1; the first end of the fuse F1 is connected to the input power circuit 01, and the second end of the fuse F1 is connected to the The rectifier circuit 11 is connected.

In one embodiment, the rectifier circuit 11 includes a rectifier bridge DB1. When the input power supply circuit 01 is connected to an AC power supply voltage signal, it can convert a 50Hz sine wave AC power into a unidirectional pulsating DC voltage/current with a frequency of 100Hz. , and the voltage range obtained after rectifying AC 198-264V is 279-373.4V; at the same time, when the input power circuit 01 is connected to the DC power supply voltage signal provided by the lighting emergency DC power supply, such as DC 198-264V, it can The power supply voltage signal is subjected to rectification processing such as anti-reverse connection to generate a rectified voltage signal.

Referring to FIG. 6, in one embodiment, the voltage sampling circuit 13 includes: a first diode D1, a second diode D2, a first capacitor C1, a first resistor R1, and a second resistor R2; The anode of a diode D1 is connected to the rectifier circuit 11, the cathode of the first diode D1 is connected to the first end of the first resistor R1 and the first end of the first capacitor C1, and the second end of the first capacitor C1 is connected to the first end of the first resistor R1 and the first end of the first capacitor C1. The power supply is connected to ground, the second end of the first resistor R1 is connected to the first end of the second resistor R2, the second end of the second resistor R2 is connected to the anode of the second diode D2, and the cathode of the second diode D2 Connected to the comparison circuit 14 .

In the specific implementation, the anode of the first diode D1 is connected to the positive output end of the rectifier circuit 11 , the voltage sampling circuit 13 is a high-voltage sampling circuit, and is a rectified voltage signal after filtering and noise reduction processing by the first filter circuit 20 . Perform partial pressure sampling. When the AC power supply voltage signal is connected, the first diode D1 and the first capacitor C1 stabilize and filter the rectified voltage signal, so that the pulsating DC is more stable, thereby improving the detection and sampling of the rectified voltage signal by the voltage sampling circuit 13 accuracy and stable reliability.

Referring to FIG. 6, in one embodiment, the comparison circuit 14 includes: a first comparator U3, a first field effect transistor Q4, a second capacitor C2, a third resistor R3, a third diode D3, and a fourth second pole tube D4; wherein, the non-inverting input terminal + of the first comparator U3 is connected to the reference voltage signal terminal, and the inverting input terminal - of the first comparator U3 is connected to the voltage sampling circuit 13, the first terminal of the third resistor R3 and the first terminal of the third resistor R3. The first terminal of the two capacitors C2 is connected, the power terminal VCC of the first comparator U3 is connected to the second power supply voltage terminal, the output terminal O of the first comparator U3 is connected to the gate of the first field effect transistor Q4, the first field The drain of the effect transistor Q4 is connected to the power control circuit 15, the source of the first field effect transistor Q4 is connected to the anode of the third diode D3, and the cathode of the third diode D3 is connected to the anode of the fourth diode D4 Connection, the second end of the third resistor R3, the second end of the second capacitor C2 and the cathode of the fourth diode D4 are connected to the power supply ground.

In a specific implementation, the reference voltage signal terminal provides the reference voltage signal, and the second power supply voltage terminal provides the second power supply voltage. Optionally, as shown in FIG. 6 , the power supply terminal VCC of the first comparator U3 is also connected to the reference voltage generating circuit 16, and the reference voltage generating circuit 16 generates a second power supply voltage according to the auxiliary power supply voltage, so as to provide a reference for the first comparator. U3 supplies power, avoids setting up a power supply circuit to supply power to the reference voltage generating circuit 16, the circuit structure is simple, and the cost is saved.

The inverting input terminal of the first comparator U3 is connected to the cathode of the second diode D2 to receive the voltage sampling signal output from the voltage sampling circuit 13 from the cathode of the second diode D2, and is passed through the second capacitor C2 and The RC filter circuit formed by the third resistor R3 performs filtering and noise reduction processing on the voltage sampling signal, so as to improve the accuracy of the first comparator U3 generating the power adjustment enable signal according to the voltage comparison signal and the reference voltage signal. The voltage value of the power adjustment enable signal is the sum of the resulting voltage values of the third diode D3 and the fourth diode D4.

Referring to FIG. 6, in one embodiment, the reference voltage generating circuit 16 includes an eighth diode D8, a seventeenth resistor R17, an eighteenth resistor R18, a first voltage regulator chip U2 and a ninth capacitor C9; wherein , the anode of the eighth diode D8 is connected to the transformer power conversion circuit 12, the cathode of the eighth diode D8 is connected to the first end of the seventeenth resistor R17, and the second end of the seventeenth resistor R17 is connected to the comparison circuit 14. The first end of the eighteenth resistor R18 is connected to the first end of the ninth capacitor C9, the second end of the ninth capacitor C9 is connected to the power supply ground, the second end of the eighteenth resistor R18, the first voltage regulator chip The cathode of U2 and the reference terminal of the first voltage regulator chip U2 are connected to the comparison circuit 14 in common, and the anode of the first voltage regulator chip U2 is connected to the power ground.

In a specific implementation, the cathode of the first voltage regulator chip U2 is the reference voltage output terminal of the reference voltage generating circuit 16, and outputs the reference voltage signal to the non-inverting input terminal + of the first comparator U3. The second terminal of the seventeenth resistor R17 outputs the second power supply voltage to the power terminal VCC of the first comparator U3 to supply power to the first comparator U3.

Referring to FIG. 6 , in one embodiment, the power control circuit 15 includes: a power control chip U1 , a third capacitor C3 , a fourth capacitor C4 , a fifth capacitor C5 , a sixth capacitor C6 , a seventh capacitor C7 , and a fifth capacitor C7 . diode D5, fourth resistor R4, fifth resistor R5, sixth resistor R6, seventh resistor R7, eighth resistor R8, ninth resistor R9 and tenth resistor R10; wherein, the compensation terminal COMP of the power control chip U1 Connect to the first end of the fourth resistor R4 and the first end of the third capacitor C3, the second end of the fourth resistor R4 is connected to the first end of the fourth capacitor C4, the second end of the third capacitor C3 and the fourth The second end of the capacitor C4 is connected to the power ground, and the voltage divider network end ZCS of the power control chip U1 is connected to the first end of the fifth capacitor C5, the second end of the fifth resistor R5 and the first end of the sixth resistor R6, The first end of the fifth resistor R5 is connected to the transformer power conversion circuit 12, the second end of the sixth resistor R6 and the second end of the fifth capacitor C5 are connected to the power supply ground, and the current sensing end ISEN of the power control chip U1 is connected to the power supply ground. The first end of the seventh resistor R7 is connected, the ground end GND of the power control chip U1 is connected to the power supply ground, the analog dimming end ADIM of the power control chip U1 is connected to the first end of the seventh capacitor C7 and the comparison circuit 14, the seventh The second end of the capacitor C7 is connected to the power supply ground, the input voltage terminal VIN of the power control chip U1 is connected to the first end of the sixth capacitor C6 and the voltage dividing power supply circuit 17, and the second end of the sixth capacitor C6 is connected to the power supply ground, The driving terminal DRV of the power control chip U1 is connected to the first terminal of the eighth resistor R8 and the cathode of the fifth diode D5, the second terminal of the eighth resistor R8, the anode of the fifth diode D5 and the ninth resistor R9 The first end of the resistor R10 is connected to the transformer power conversion circuit 12 in common, the second end of the ninth resistor R9, the second end of the seventh resistor R7 and the first end of the tenth resistor R10 are connected to the transformer power conversion circuit 12 in common. The second end of the tenth resistor R10 is connected to the power ground.

In the specific implementation, the third capacitor C3, the fourth capacitor C4 and the fourth resistor R4 together constitute the RC filter circuit of the power control chip U1, which is the compensation network of the power control chip U1, which can make the power control chip U1 work stably and reliably . The first end of the fifth resistor R5 is connected to the transformer power conversion circuit 12 to access the auxiliary power supply voltage output by the transformer power patent circuit 12, so as to detect that the transformer power conversion circuit 12 performs voltage conversion processing on the rectified voltage signal to The condition of generating the drive voltage signal and the auxiliary supply voltage forms a feedback detection that adjusts the power of the drive voltage signal. The eighth resistor R8 and the fifth diode D5 can perform current limiting protection and anti-reverse connection protection on the driving control signal, so as to protect components such as the power control chip U1 from overcurrent damage. The analog dimming terminal ADIM of the power control chip U1 inputs the power adjustment enable signal, and the seventh capacitor C7 filters the power adjustment enable signal. The power adjustment enable signal input to the analog dimming terminal ADIM of the power control chip U1 The voltage value range is 0-3.3V. When the adjustment driving voltage signal is full load power (that is, rated power), the voltage value of the power adjustment enable signal input by the analog dimming terminal ADIM of the power control chip U1 is 3.3V, and the power Please refer to Figure 7 for the dimming curve of the control chip U1. Figure 7 shows the relationship between the voltage value of the power adjustment enable signal input by the analog dimming terminal ADIM of the power control chip U1 and the percentage of the power that adjusts the driving voltage signal. , 3.3V is the voltage value of the power adjustment enable signal corresponding to the full load power, 3.3V*20%=0.66V, which is exactly two diodes connected in series (ie the third diode D3 and the fourth diode D4) The sum of the turn-on voltage and buck drop. The voltage dividing power supply circuit 17 generates a first power supply voltage to supply power to the power control chip U1.

In one embodiment, please refer to FIG. 6 , the voltage dividing power supply circuit 17 includes a fifteenth resistor R15, a sixteenth resistor R16 and a seventh diode D7; the first end of the fifteenth resistor R15 is connected to the rectifier circuit , the second end of the fifteenth resistor R15 and the first end of the sixteenth resistor R16 are connected to the power control circuit 15 in common, the second end of the sixteenth resistor R16 is connected to the cathode of the seventh diode D7, the seventh The anode of the diode D7 is connected to the reference voltage generating circuit.

In this embodiment, the rectified voltage signal is divided by the fifteenth resistor R15, and the auxiliary power supply voltage is divided by the sixteenth resistor R16 and the seventh diode D7, so as to obtain the second power supply voltage, which is passed through The sixth capacitor C6 performs filtering and noise reduction processing on the first power supply voltage, and outputs it to the input voltage terminal VIN of the power control chip U1 to supply power to the power control chip U1.

Referring to FIG. 6, in one embodiment, the variable voltage power conversion circuit 12 includes: a transformer T1, an eighth capacitor C8, a sixth diode D6, an eleventh resistor R11, a twelfth resistor R12, and a second field Effect transistor Q2; wherein, the first end of the primary winding T1-A of the transformer T1 is connected to the rectifier circuit 11 and the load 100, and the second end of the primary winding T1-A of the transformer T1 is connected to the first end of the eighth capacitor C8 , the anode of the sixth diode D6 and the drain of the second field effect transistor Q2 are connected, the source of the second field effect transistor Q2, the gate of the second field effect transistor Q2 and the first end of the twelfth resistor R12 Commonly connected to the power control circuit 15, the second end of the twelfth resistor R12 is connected to the power supply ground, the second end of the eighth capacitor C8 is connected to the first end of the eleventh resistor R11, and the cathode of the sixth diode D6 The second end of the eleventh resistor R11 is connected to the load 100 in common, the first end of the secondary winding T1-AB of the transformer T1 is connected to the power control circuit 15, and the second end of the secondary winding T1-AB of the transformer T1 is connected to the power control circuit 15. Power ground connection.

In a specific implementation, the first end of the secondary winding T1 -AB of the transformer T1 is also connected to the reference voltage generating circuit 16 , so as to output the auxiliary power supply voltage to the reference voltage generating circuit 16 . The gate of the second field effect transistor Q2 is the driving control signal input end of the patented circuit 12 of the transformer power. The second end of the eighth resistor R8, the anode of the fifth diode D5 and the first end of the ninth resistor R9 are connected to the gate of the second field effect transistor Q2, and the power control chip U1 adjusts the output to the second field effect transistor The duty ratio of the drive control signal of the gate of the transistor Q2 is adjusted, so as to adjust the drive voltage signal output to the load LED, thereby realizing the adjustment of the power corresponding to the drive voltage signal.

The following will briefly describe the working principle of the AC-DC switching lighting drive circuit with reference to Figure 6:

When the input power circuit 11 provides an AC power voltage signal (ie, AC 198-264V), after rectification by the rectifier bridge DB1, a pulsating DC voltage with a voltage value range of 279-373.4V is obtained, which is greater than the DC provided by the lighting emergency system. The power supply voltage signal (ie DC 198-264V), so that the voltage sampling signal generated after sampling the rectified voltage signal by the voltage sampling circuit 13 is higher than the reference voltage 2.5V (ie the reference voltage signal), that is, the first comparator U3 The voltage of the inverting input terminal - of the first comparator U3 is higher than the non-inverting input terminal of the first comparator U3 + the corresponding reference voltage of 2.5V, the first comparator U3 outputs a low level to control the first field effect transistor Q4 to be turned off, and the power control chip U1 The analog dimming terminal ADIM is high level, and the power control chip U1 is not enabled to generate the drive control signal; when the input power circuit 01 is switched to connect to the DC power supply voltage signal (ie DC 198-264V) provided by the lighting emergency system, The voltage sampling circuit 13 samples the rectified voltage signal and generates a voltage sampling signal low-voltage reference voltage signal, the voltage of the inverting input terminal - of the first comparator U3 is lower than the non-inverting input terminal of the first comparator U3 + the corresponding reference voltage 2.5 V, the first comparator U3 inverts and outputs a high level to drive the first FET Q4 to turn on, pull down the level of the analog dimming terminal ADIM of the power control chip U1, and the analog dimming terminal ADIM of the power control chip U1 In the low-level state, the power control chip U1 is enabled to output a drive control signal, so as to adjust the power corresponding to the drive voltage signal output to the load 100 (LED) through the second field effect transistor 2 and the transformer T1. According to the dimming characteristics of the analog dimming terminal ADIM of the power control chip U1, the power adjustment enable signal with a voltage value of 0.6-0.7V is exactly 20% of the full load power, using two diodes (ie the third diode D3 and The fourth diode D4) is connected in series to realize the function of low-cost automatic conversion of emergency DC power supply and reducing the working power of the load 100 when the emergency DC power supply is supplied, and also conforms to the emergency lighting system design specification standard.

A second aspect of the present application provides a lighting fixture comprising the AC-DC switching lighting driving circuit according to any one of the above.

In the specific implementation, the lamps can be LED lamps, including LED lamps, etc., which can be powered by the connected AC mains for full-load lighting, or can be powered by the emergency direct current provided by the connected emergency direct current power supply for lighting. Lighting and lighting, and the power adjustment of the lighting driving voltage signal can be performed when the emergency DC power supply for lighting is connected, thereby saving energy consumption and prolonging the use time of the emergency DC power supply.

The embodiment of the present application can realize that when the AC mains is connected, the driving voltage signal of full load power is output to supply power to the load; when the DC power supply voltage provided by the lighting emergency DC power supply is connected, the power corresponding to the output driving voltage signal is adjusted. , to realize that LED lamps can be used when connected to different power sources; at the same time, when connected to the emergency lighting DC power supply for use, the power of the driving lamps can be adjusted, the lighting power consumption can be reduced, the use time of the emergency DC power supply can be prolonged, and the emergency DC power supply can be used. The lighting system design specification standard saves the cost and improves the practicability of the lighting driving power circuit.

The above are only optional embodiments of the present application, and are not intended to limit the present application. Various modifications and variations of this application are possible for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the scope of the claims of this application.

Claims

An AC-DC switching lighting driving circuit, which is connected to a load, characterized in that the AC-DC switching lighting driving circuit comprises:

an input power circuit configured to provide a power supply voltage signal;

a rectification circuit, connected to the input power supply circuit, and configured to perform rectification processing on the power supply voltage signal to generate a rectified voltage signal;

A transformer power conversion circuit, connected to the rectification circuit, is configured to perform voltage conversion processing on the rectified voltage signal to generate a driving voltage signal, and adjust the driving voltage signal according to a driving control signal; the driving voltage signal for driving the load for lighting;

a voltage sampling circuit, connected to the rectification circuit, configured to perform voltage sampling on the rectified voltage signal to generate a voltage sampling signal;

a comparison circuit, connected to the voltage sampling circuit, configured to generate a power adjustment enable signal according to the voltage sampling signal being lower than a reference voltage signal;

A power control circuit, connected to the comparison circuit and the transformer power conversion circuit, is configured to generate the drive control signal according to the power adjustment enable signal.
The AC-DC switching lighting drive circuit according to claim 1, wherein the transformer power conversion circuit is further configured to perform voltage conversion processing on the rectified voltage signal to generate an auxiliary power supply voltage;

The AC-DC switching lighting drive circuit further includes:

A reference voltage generation circuit, connected to the transformer power conversion circuit and the comparison circuit, is configured to generate the reference voltage signal according to the auxiliary power supply voltage.
The AC-DC switching lighting driving circuit according to claim 2, wherein the AC-DC switching lighting driving circuit further comprises:

a voltage divider power supply circuit, connected to the rectifier circuit, the transformer power conversion circuit and the power control circuit, and configured to generate a first power supply voltage according to the rectified voltage signal and the auxiliary power supply voltage, to Power control circuit power supply.
The AC-DC switching lighting drive circuit according to claim 1, wherein the AC-DC switching lighting driving circuit further comprises:

A protection circuit, connected to the input power supply circuit and the rectifier circuit, is configured to perform overcurrent protection and overtemperature protection on the power supply voltage signal.
The AC-DC switching lighting driving circuit according to claim 4, wherein the AC-DC switching lighting driving circuit further comprises:

an electromagnetic filter circuit, connected to the protection circuit and the rectifier circuit, and configured to perform electromagnetic interference suppression processing on the power supply voltage signal after overcurrent protection and overtemperature protection;

a first filter circuit, connected to the rectifier circuit and the voltage sampling circuit, and configured to perform filtering and noise reduction processing on the rectified voltage signal;

A second filter circuit, connected to the transformer power conversion circuit and the load, is configured to perform filtering and noise reduction processing on the driving voltage signal.
The AC-DC switching lighting driving circuit according to claim 1, wherein the voltage sampling circuit comprises: a first diode, a second diode, a first capacitor, a first resistor and a second resistor; wherein , the anode of the first diode is connected to the rectifier circuit, the cathode of the first diode is connected to the first end of the first resistor and the first end of the first capacitor, the The second end of the first capacitor is connected to the power ground, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the second diode The anode is connected to the second diode, and the cathode of the second diode is connected to the comparison circuit.
The AC-DC switching lighting driving circuit according to claim 1, wherein the comparison circuit comprises: a first comparator, a first field effect transistor, a second capacitor, a third resistor, a third diode and a first Four diodes; wherein, the non-inverting input terminal of the first comparator is connected to the reference voltage signal terminal, and the inverting input terminal of the first comparator is connected to the voltage sampling circuit and the first terminal of the third resistor. terminal and the first terminal of the second capacitor, the power terminal of the first comparator is connected to the second power supply voltage terminal, the output terminal of the first comparator is connected to the gate of the first field effect transistor connected, the drain of the first field effect transistor is connected to the power control circuit, the source of the first field effect transistor is connected to the anode of the third diode, and the third diode The cathode is connected to the anode of the fourth diode, and the second end of the third resistor, the second end of the second capacitor and the cathode of the fourth diode are connected to the power ground.
The AC-DC switching lighting drive circuit according to claim 1, wherein the power control circuit comprises: a power control chip, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, and a third capacitor. Five diodes, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor; wherein the compensation terminal of the power control chip and the fourth resistor The first end is connected to the first end of the third capacitor, the second end of the fourth resistor is connected to the first end of the fourth capacitor, and the second end of the third capacitor is connected to the fourth The second end of the capacitor is connected to the power ground, the voltage divider network end of the power control chip is connected to the first end of the fifth capacitor, the second end of the fifth resistor and the first end of the sixth resistor connection, the first end of the fifth resistor is connected to the transformer power conversion circuit, the second end of the sixth resistor and the second end of the fifth capacitor are connected to the power supply ground, and the power control chip The current sensing terminal of the power control chip is connected to the first terminal of the seventh resistor, the ground terminal of the power control chip is connected to the power supply ground, and the analog dimming terminal of the power control chip is connected to the first terminal of the seventh capacitor is connected to the comparison circuit, the second end of the seventh capacitor is connected to the power supply ground, the input voltage end of the power control chip is connected to the first end of the sixth capacitor and the voltage divider power supply circuit, the The second end of the six capacitors is connected to the power supply ground, the driving end of the power control chip is connected to the first end of the eighth resistor and the cathode of the fifth diode, and the second end of the eighth resistor is connected , the anode of the fifth diode and the first end of the ninth resistor are connected to the transformer power conversion circuit, the second end of the ninth resistor and the second end of the seventh resistor and the first end of the tenth resistor is commonly connected to the variable voltage power conversion circuit, and the second end of the tenth resistor is connected to the power ground.
The AC-DC switching lighting drive circuit according to claim 1, wherein the transformer power conversion circuit comprises: a transformer, an eighth capacitor, a sixth diode, an eleventh resistor, a twelfth resistor, and a first Two field effect transistors; wherein the first end of the primary winding of the transformer is connected to the rectifier circuit and the load, and the second end of the primary winding of the transformer is connected to the first end of the eighth capacitor , the anode of the sixth diode and the drain of the second field effect transistor are connected, the source of the second field effect transistor, the gate of the second field effect transistor and the twelfth field effect transistor are connected The first end of the resistor is connected to the power control circuit in common, the second end of the twelfth resistor is connected to the power supply ground, and the second end of the eighth capacitor is connected to the first end of the eleventh resistor , the cathode of the sixth diode and the second end of the eleventh resistor are connected to the load in common, the first end of the secondary winding of the transformer is connected to the power control circuit, and the transformer The second end of the secondary winding is connected to the power ground.
The AC-DC switching lighting driving circuit according to claim 2, wherein the reference voltage generating circuit comprises an eighth diode, a thirteenth resistor, a fourteenth resistor, a first voltage regulator chip and a ninth capacitor; wherein , the anode of the eighth diode is connected to the transformer power conversion circuit, the cathode of the eighth diode is connected to the first end of the thirteenth resistor, the second end of the thirteenth resistor is connected to the comparison circuit, the fourteenth resistor The first end of the ninth capacitor is connected to the first end of the ninth capacitor, the second end of the ninth capacitor is connected to the power supply ground, the second end of the fourteenth resistor, the cathode of the first voltage regulator chip and the reference of the first voltage regulator chip The terminals are connected to the comparison circuit in common, and the anode of the first voltage regulator chip is connected to the power ground.
The AC-DC switching lighting drive circuit according to claim 3, wherein the voltage dividing power supply circuit comprises a fifteenth resistor, a sixteenth resistor and a seventh diode; the first end of the fifteenth resistor is connected to the rectifier circuit connection, the second end of the fifteenth resistor and the first end of the sixteenth resistor are connected to the power control circuit, the second end of the sixteenth resistor is connected to the cathode of the seventh diode, and the seventh diode The anode is connected to the reference voltage generating circuit.
The AC-DC switching lighting drive circuit according to claim 5, wherein the electromagnetic filter circuit comprises: a first inductor, a thirteenth resistor, a fourteenth resistor, a second inductor, a first variable resistor and a first filter capacitor;

The first end of the first inductor, the first end of the thirteenth resistor, and the first end of the first filter capacitor are connected to the input power circuit in common, and the second end of the first inductor, The second end of the thirteenth resistor and the first end of the first variable resistor are commonly connected to the rectifier circuit, the second end of the first filter capacitor, and the first end of the fourteenth resistor. One end and the first end of the second inductor are commonly connected to the input power circuit, the second end of the second inductor, the second end of the fourteenth resistor and the first variable resistor The second end of the rectifier is commonly connected to the rectifier circuit.
The AC-DC switching lighting driving circuit according to claim 5, wherein the first filter circuit comprises a second filter capacitor; the first end of the second filter capacitor and the first output end of the rectifier circuit connected, and the second end of the second filter capacitor is connected to the second output end of the rectifier circuit.
The AC-DC switching lighting drive circuit according to claim 5, wherein the second filter circuit comprises a third filter capacitor and a seventeenth resistor; the first end of the third filter capacitor is connected to the tenth The first end of the seven resistors is commonly connected to the first end of the load, and the second end of the third filter capacitor and the second end of the seventeenth resistor shown are commonly connected to the second end of the load.
The AC-DC switching lighting driving circuit according to claim 1, wherein the rectifier circuit comprises a rectifier bridge; the first input end of the rectifier bridge is connected to the first output end of the input power supply circuit, and the The second input end of the rectifier bridge is connected to the second output end of the input power supply circuit, the first output end of the rectifier circuit is connected to the first end of the load, and the output end of the second end of the rectifier circuit is grounded .
The AC-DC switching lighting drive circuit according to claim 4, wherein the protection circuit comprises a fuse; a first end of the fuse is connected to the input power circuit, and a second end of the fuse is connected to the input power circuit. Rectifier circuit connection.
A lamp, characterized in that the lamp comprises the AC-DC switching lighting drive circuit according to any one of claims 1 to 16.