CN113329543A - Dimming circuit capable of stabilizing output voltage - Google Patents
Dimming circuit capable of stabilizing output voltage Download PDFInfo
- Publication number
- CN113329543A CN113329543A CN202110638065.9A CN202110638065A CN113329543A CN 113329543 A CN113329543 A CN 113329543A CN 202110638065 A CN202110638065 A CN 202110638065A CN 113329543 A CN113329543 A CN 113329543A
- Authority
- CN
- China
- Prior art keywords
- voltage
- module
- output
- chip
- resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/30—Driver circuits
- H05B45/34—Voltage stabilisation; Maintaining constant voltage
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/10—Controlling the intensity of the light
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
- H05B47/10—Controlling the light source
- H05B47/175—Controlling the light source by remote control
- H05B47/19—Controlling the light source by remote control via wireless transmission
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
The invention discloses a dimming circuit capable of stabilizing output voltage, which comprises a rectifying and filtering module, a boosting and dimming constant current module, a voltage output module and an LED load, and is characterized by also comprising a voltage stabilizing control module; the LED light source comprises a rectification filter module, a voltage output module, a voltage stabilizing control module, a voltage boosting and dimming constant current module, a voltage stabilizing control module and an LED load, wherein the input end of the rectification filter module is connected with commercial power, the output end of the rectification filter module is connected with the input end of the voltage output module, the voltage boosting and dimming constant current module is connected with the voltage output module, the output end of the voltage output module is connected with the voltage stabilizing control module, the voltage stabilizing output module controls the voltage boosting and dimming constant current module through a PWM signal, and the voltage stabilizing control module is connected with the LED load. The LED load voltage stabilizing circuit is provided with the MOS tube connected with the LED load, and the voltage reduction of the load LED load is compensated by controlling the voltage drop change of the MOS tube, so that the purpose of stabilizing the output voltage is achieved.
Description
Technical Field
The invention relates to the technical field of LED lighting, in particular to a dimming circuit capable of stabilizing output voltage.
Background
The illumination plays an indispensable role in daily life of people, so that people can see things clearly, and convenience is brought to life and work of people. In recent years, with the attention paid to energy and environmental issues and the improvement of life quality, the lighting is no longer limited to single-brightness lighting, and the dimming lighting device is produced under the trend of various brightness lighting requirements.
A 'switch dimming circuit' disclosed in Chinese patent literature, with publication number CN106714411A and publication date 2017-05-24, comprises a power switch and a driving circuit. The driving circuit comprises a power module, an energy storage module and a control module. The power supply module is used for converting alternating-current voltage output by the alternating-current power supply into direct-current voltage. The control module comprises a first switch tube and a control device. The control device is used for controlling the on-off of the first switching tube so as to control the power supply module to charge the energy storage module or discharge the energy storage module. The control device is used for detecting the discharge end pulse of the energy storage module and controlling the first switch tube to be switched on or switched off according to the line current flowing through the first switch tube and the discharge end pulse. The control device is used for judging the power switch to be switched off and closing the control device when the discharging end pulse is not detected within preset time. The switch dimming circuit can accurately adjust the brightness of the light source. However, after dimming, the voltage of the LED string is reduced due to the reduction of the output current, and when the voltage is reduced to a certain degree, the circuit cannot stably operate.
Disclosure of Invention
The invention aims to solve the problem that when a dimming circuit in the prior art is used for dimming, the output voltage is reduced due to the reduction of the output current, so that the circuit cannot work stably, and provides the dimming circuit capable of stabilizing the output voltage.
In order to achieve the purpose, the invention adopts the following technical scheme:
a dimming circuit capable of stabilizing output voltage comprises a rectifying and filtering module, a boosting and dimming constant current module and a voltage output module, and is characterized by further comprising a voltage stabilization control module; the input end of the rectification filter module is connected with a mains supply, the output end of the rectification filter module is connected with the input end of the voltage output module, the boosting dimming constant current module is connected with the voltage output module, the output end of the voltage output module is connected with the voltage stabilizing control module, the voltage stabilizing output module controls the boosting dimming constant current module through a PWM signal, and the voltage stabilizing control module is connected with a load.
The rectifier filter module converts the input commercial power from alternating current power to direct current power after filtering and rectifying, the boost dimming constant current module performs a boost function on the circuit and realizes the control of constant current and dimming of the circuit, the voltage output module is responsible for stable voltage output to supply power to the load lamp string, and the voltage stabilization control module is the key point of the invention and plays a role in stabilizing output voltage by arranging the MOS tube connected with the LED lamp string and adjusting.
Preferably, the voltage stabilization control module includes a chip U2, a power supply pin of the chip U2 is connected to a module power supply voltage, a voltage detection end of the chip U2 is connected to one end of a resistor R4 and one end of a resistor R5, the other end of the resistor R4 is connected to an output end of the voltage output module and an input end of a load, the other end of the resistor R5 is connected to a source of a MOS transistor Q2 and is grounded, a drain of the MOS transistor Q2 is connected to an output end of the load, a gate of the MOS transistor Q2 is connected to one end of a resistor R6 and one end of a capacitor C4, the other end of the capacitor C4 is grounded, the MOS transistor Q2 stabilizes an output voltage by adjusting a voltage drop between the drain and the source, the other end of the resistor R6 is connected to a first signal output end of the chip U2, and a second signal output end of the chip U2 outputs a PWM signal to the chip U1.
In the voltage stabilizing control module, the chip U2 controls the dimming of the voltage boosting dimming constant current module by outputting a PWM dimming signal, a voltage detection end of the chip U2 can convert a voltage sampled in a circuit from an analog signal into a digital signal and input the digital signal into the chip, and a first signal output end of the chip U2 can output a control signal to control the grid voltage of the MOS tube Q2 so as to control the voltage drop of a drain electrode and a source electrode of the MOS tube Q2, thereby compensating the reduced voltage of the LED lamp string during the dimming process and ensuring the stability of the output voltage.
Preferably, the chip U2 is a radio frequency control chip, and can use a remote controller or APP to implement a control function. The chip U2 of wireless control module group is integrated with the transceiving function and the MCU function of wireless communication protocol to realize contactless intelligent control, its wireless communication mode can select for use WIFI, BLE or ZIGBEE.
Preferably, the voltage output module comprises an electrolytic capacitor C3, the anode of the electrolytic capacitor C3 is connected with the cathode of the diode D1 and is connected with the other end of the resistor R4, the cathode of the electrolytic capacitor C3 is connected with the other end of the resistor R5 and is grounded, the anode of the diode D1 is connected with one end of the inductor L2A and is connected with the drain of the MOS transistor Q1, and the other end of the inductor L2A is connected with the output end of the rectifying and filtering circuit.
The inductor L2A is an energy storage inductor which can store electric energy, and forms a step-down transformer with the secondary inductor L2B, the diode D1 is the output direction of the output diode control voltage, and the two ends of the electrolytic capacitor C3 are the output voltage of the circuit, so that the purpose of the invention is to ensure the voltage stability of the two ends of the electrolytic capacitor C3.
Preferably, the boost dimming constant current module comprises a chip U1, a driving terminal of the chip U1 is connected to a gate of a MOS transistor Q1, a drain of the MOS transistor Q1 is connected to an anode of a diode D1, a source of the MOS transistor Q1 is connected to a current detection terminal of a chip U1 and is grounded through a resistor R3, the other end of a secondary inductor L2B is connected to an anode of a diode D2 and is grounded, one end of the secondary inductor L2B is connected to a cathode of a diode D2, an anode of the diode D3 and one end of a resistor R1, a cathode of a diode D3 is connected to one end of a capacitor C5 and is connected to a voltage input terminal of the chip U1, the other end of the resistor R1 is connected to one end of a resistor R2 and is connected to a feedback terminal of the chip U1, a compensation terminal of the chip U1 is grounded through a capacitor C6, and a ground terminal of the chip U1 is connected to the other end of the capacitor C5 and the other end of the resistor R2.
In the boost dimming constant current module, the secondary inductor L2B supplies power to the chip U1 and provides feedback of output voltage, and the chip U1 receives a PWM dimming signal from the chip U2 to perform dimming operation. The driving end of the chip U1 controls the on-off of the MOS transistor Q1 to realize constant current control, and the current detection end of the chip U1 is responsible for detecting the current passing through the resistor R3.
Preferably, the rectification filter module comprises a filter unit and a rectification unit, the input end of the filter unit is connected to the mains supply, the output end of the filter unit is connected to the input end of the rectification unit, the output end of the rectification unit is connected to one end of the capacitor C7 and connected to the input end of the voltage output module, and the other end of the capacitor C7 is grounded. The filtering unit is a pi-type filter, the rectifying unit is a rectifier bridge, and alternating current electric energy is converted into direct current electric energy to be input into the circuit after filtering, rectifying and filtering operations.
Preferably, the load is an LED lamp string, an input end of the LED lamp string is connected to the other end of the resistor R4, and an output end of the LED lamp string is connected to a drain of the MOS transistor Q2.
Preferably, the dimming circuit further comprises a circuit protection unit, and the circuit protection unit is connected between the input end of the rectifying and filtering circuit and the mains supply input. The circuit protection unit is a fuse, and the fuse is connected on the live wire of rectifier filter circuit input, and when commercial power input exceeded the fuse bearing capacity, thereby the fuse disconnection made the circuit stop work protection circuit.
The invention has the beneficial effects that: the voltage stabilization control module is arranged to regulate and control the voltage drop between the drain electrode and the source electrode of the MOS tube by controlling the grid voltage of the MOS tube, so that the voltage reduction during dimming of the LED lamp string is compensated, and the output voltage of the circuit is always kept stable; the voltage stabilization control module selects the wireless control module as a control chip, can use a remote controller or a mobile phone APP to control operation, and is more convenient for people to use.
Drawings
FIG. 1 is a block circuit diagram of the present invention;
FIG. 2 is a circuit schematic of the present invention;
FIG. 3 is a graph showing voltage variations of LED light strings during dimming according to an embodiment of the present invention;
FIG. 4 is a graph of output voltage control variation during dimming according to an embodiment of the present invention;
in the figure: 1. the voltage across the electrolytic capacitor C3 (output voltage); 2. LED lamp string voltage; 3. the drain-source Voltage (VDS) of the MOS transistor Q2; 4. the MOS transistor Q2 has a voltage between the gate and the source (VGS).
Detailed Description
The invention is further described with reference to the following figures and detailed description.
As shown in fig. 1, a dimming circuit capable of stabilizing output voltage includes a rectifying and filtering module, a boosting and dimming constant current module, a voltage output module, a voltage stabilization control module and an LED load; the LED light source comprises a rectification filter module, a voltage output module, a voltage stabilizing control module, a voltage boosting and dimming constant current module, a voltage stabilizing control module and an LED load, wherein the input end of the rectification filter module is connected with commercial power, the output end of the rectification filter module is connected with the input end of the voltage output module, the voltage boosting and dimming constant current module and the voltage output module are connected, the output end of the voltage output module is connected with the voltage stabilizing control module, the voltage stabilizing output module controls the voltage boosting and dimming constant current module through a PWM signal, and the voltage stabilizing control module is connected with the LED load.
As shown in fig. 2, the regulator control module a4 includes a chip U2, and in this embodiment, the chip U2 is a low power zigbee3.0 module of BWMZB02 type, and is composed of a highly integrated wireless rf chip EFR32MG13F732 and a small number of peripheral circuits. A 3.3V power supply pin of a chip U2 is connected to a 3.3V module power supply voltage, an ADC pin of the chip U2 is connected to one end of a resistor R4 and one end of a resistor R5, the other end of the resistor R4 is connected to an output end of a voltage output module and to an input end of a load, the other end of the resistor R5 is connected to a source of a MOS transistor Q2 and to ground, a drain of the MOS transistor Q2 is connected to an output end of the load, a gate of the MOS transistor Q2 is connected to one end of a resistor R6 and one end of a capacitor C4, the other end of the capacitor C4 is grounded, the MOS transistor Q2 stabilizes an output voltage by adjusting a voltage drop VDS between the drain and the source, the other end of the resistor R6 is connected to a PWM _ W pin of the chip U2, and a PWM _ C pin of the chip U2 outputs a PWM signal to the chip U1.
The voltage output module A2 comprises an electrolytic capacitor C3, the anode of the electrolytic capacitor C3 is connected with the cathode of a diode D1 and is connected with the other end of a resistor R4, the cathode of the electrolytic capacitor C3 is connected with the other end of a resistor R5 and is grounded, the anode of the diode D1 is connected with the No. 2 port of an inductor L2A and is connected with the drain of a MOS transistor Q1, and the No. 1 port of the inductor L2A is connected with the output end of a rectifying and filtering circuit.
The boost dimming constant current module a3 includes a chip U1, and in this embodiment, the chip U1 is an integrated circuit chip of JW1606 type. The GATE pin of the chip U1 is connected to the GATE of the MOS transistor Q1, the drain of the MOS transistor Q1 is connected to the anode of the diode D1, the source of the MOS transistor Q1 is connected to the SNP pin of the chip U1 and is grounded through the resistor R3, the port No. 3 of the secondary inductor L2B is connected to the anode of the diode D2 and is grounded, the port No. 3 of the secondary inductor L2B and the port No. 1 of the inductor L2A are named ends, the port No. 4 of the secondary inductor L2B is connected to the cathode of the diode D2, the anode of the diode D3 and one end of the resistor R1, the cathode of the diode D3 is connected to one end of the capacitor C5 and to the VCC pin of the chip U1, the other end of the resistor R1 is connected to one end of the resistor R2 and to the FB terminal of the chip U1, the COMP pin of the chip U1 is grounded through the capacitor C1, and the ground terminal of the other end of the capacitor C1 and the ground.
The rectification and filtering module A1 comprises a filtering unit and a rectification unit, wherein the filtering unit is a pi-type filter, one end of an inductor L1 is connected with one end of a capacitor C1 on a live wire, the other end of the inductor L1 is connected with one end of a capacitor C2, and the other end of a capacitor C1 is connected with the other end of a capacitor C2 and connected on a zero wire. The rectifying unit is a rectifying bridge, the No. 1 end of the rectifying bridge BS1 is connected with one end of the capacitor C2, and the No. 3 end of the rectifying bridge BS1 is connected with the other end of the capacitor C2; no. 2 terminal of the rectifier bridge BS1 is connected with one end of the capacitor C7 and connected with the No. 1 port of the inductor L2A, and the No. 4 terminal of the rectifier bridge BS1 and the other end of the capacitor C7 are both grounded.
One end of the fuse F1 is connected with the mains supply, and the other end is connected with one end of the inductor L1
The LED load A5 is an LED lamp string, the input end of the LED lamp string is connected with the other end of the resistor R4, and the output end of the LED lamp string is connected with the drain electrode of the MOS tube Q2.
The rectifier filter module converts the input commercial power from alternating current power to direct current power after filtering and rectifying, the boost dimming constant current module performs a boost function on the circuit and realizes the control of constant current and dimming of the circuit, the voltage output module is responsible for stable voltage output to supply power to the load lamp string, and the voltage stabilization control module is the key point of the invention and plays a role in stabilizing output voltage by arranging the MOS tube connected with the LED lamp string and adjusting.
In the voltage stabilizing control module, the chip U2 controls dimming of the boost dimming constant current module by outputting a PWM dimming signal. The ADC pin can convert the voltage sampled in the circuit from an analog signal to a digital signal and input the digital signal into a chip, and the resistor R4 and the resistor R5 are voltage dividing resistors and can be used for sampling the voltage. The PWM _ W pin of the chip U2 can output a control signal to control the gate voltage VGS of the MOS transistor Q2 to control the voltage drop VGS of the drain and the source thereof, so as to compensate the voltage drop of the LED string during dimming, thereby ensuring the stability of the output voltage. Regard as chip U2 with wireless control module group, integrated wireless communication agreement's transceiver function and MCU function on it to realize contactless intelligent control, its wireless communication mode not only can choose ZIGBEE for use, can also choose for use WIFI or BLE, makes the user can realize long-range intelligent control through telecommuter or cell-phone APP etc. and it is more convenient to operate.
The inductor L2A in the voltage output module is an energy storage inductor which can store electric energy, and forms a step-down transformer with the secondary inductor L2B, the diode D1 is an output diode which can control the output direction of voltage, and the two ends of the electrolytic capacitor C3 are the output voltage of the circuit, the invention aims to ensure the voltage stability of the two ends of the electrolytic capacitor C3.
In the boost dimming constant current module, a secondary inductor L2B supplies power to a chip U1 and provides feedback of output voltage, a diode D2 is a rectifier diode, and a capacitor C5 filters the power supplied to the chip U1. The chip U1 receives the PWM dimming signal from the chip U2 and performs a dimming operation. The GATE pin of the chip U1 controls the on/off of the MOS transistor Q1 to realize constant current control, and the SNP pin is responsible for detecting the current passing through the resistor R3.
The circuit protection unit is connected between the input end of the rectification filter circuit and the commercial power input. The circuit protection unit is a fuse, and the fuse is connected on the live wire of rectifier filter circuit input, and when commercial power input exceeded the fuse bearing capacity, thereby the fuse disconnection made the circuit stop work protection circuit.
In the embodiment of the invention, the commercial power input alternating voltage is converted into the direct current input voltage output module after passing through the rectifying and filtering circuit, meanwhile, due to the inductor L2A and the secondary inductor L2B, the output voltage can be input into the chip U1, the output voltage in the secondary inductor L2B can be input into a VCC port as the power supply voltage of the chip U1 after being rectified and filtered through the diode D2 and the capacitor C5, and meanwhile, the voltage can be detected through the voltage-dividing resistors R1 and R2 and input into the FB pin of the chip U1, so that the voltage output is controlled.
The voltage output module receives the rectified and filtered input voltage and outputs the rectified and filtered input voltage through an output diode D1, and the voltage at two ends of a filtering output capacitor C3 is the output voltage in the circuit and supplies power to the LED load. In the process, because the anode of the diode D1 is connected with the drain of the MOS transistor Q1, the MOS transistor Q1 is used as a power device for switching in the circuit, and the constant current control can be realized by combining the current detection resistor R3. The principle is as follows: the GATE pin is a driving pin of the MOS transistor Q1, and the output is square wave; the SNP pin is a peak current detection pin of the MOS tube, a comparator is arranged in the SNP pin, when the voltage on the resistor R3 reaches the threshold value of the comparator, the chip U1 turns off the MOS tube Q1 so as to realize constant current control, and the chip U1 and an internal circuit form linear regulation rate compensation to improve the linear regulation rate of the circuit.
The voltage output module outputs voltage to the voltage stabilization control module, and the voltage stabilization control module is connected with the LED load to enable the circuit to work. The voltage stabilization control module is used for stabilizing the output voltage.
As shown in fig. 3, when the dimming circuit is not provided with the voltage stabilizing control module, the LED load is directly connected to the voltage output module, and at this time, after the dimming operation is performed in the circuit, the voltage across the LED load is reduced from 400V for normal operation to 350V or less, and the output voltage at this time is also 350V or less, so that the circuit cannot operate stably.
Therefore, as shown in fig. 4, after the voltage stabilization control module is added, the dimming operation of the circuit is performed, the voltage across the LED load still decreases from 400V for normal operation to 350V or less, but a voltage drop VDS is generated between the drain and the source of the MOS transistor Q2 connected to the LED load and increases from 0.3V to 50V, and the output voltage is always maintained at about 400V after the two are combined, so that the circuit can operate stably.
The operating principle of the voltage stabilization control module is that firstly, the voltage division resistors R4 and R5 are used for carrying out voltage division and sampling on output voltage, the sampled voltage is input into an ADC pin of the chip U2, an analog signal is converted into a digital signal to be input, the chip U2 determines signal output of the PWM _ W pin according to detected voltage, the output PWM signal is converted into a gate voltage VGS of the true current voltage control MOS transistor Q2 through the integrating capacitor C4, and the MOS transistor Q2 is controlled to be in a conducting state or a variable resistor area to change the voltage VDS between the drain and the source through the change of the gate voltage VGS. When the LED load voltage is 400V, as shown in fig. 4 from t0 to t1, the circuit is not dimmed, and the output voltage is 400V, so that the gate voltage VGS is 3.3V to make the MOS transistor Q2 in a fully turned-on state, and the voltage drop VDS is 0.3V, which is negligible compared with 400V. After the circuit starts dimming, as shown in fig. 4 from t1 to t2, the voltage of the LED load starts to drop from 400V to 350V, in order to keep the output voltage stable at 400V, the control gate voltage VGS of the chip U2 is gradually lowered to 1.2V, so that the MOS transistor Q2 is in the variable resistance region, and during the dropping of VGS, the voltage drop VDS of the MOS transistor Q2 gradually increases from 0.3V to 50V, so that the output voltage still keeps operating at 400V.
The above-described embodiments are merely illustrative and explanatory of the present invention and are not restrictive of the invention, and any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (8)
1. A dimming circuit capable of stabilizing output voltage comprises a rectifying and filtering module, a boosting and dimming constant current module and a voltage output module, and is characterized by further comprising a voltage stabilization control module; the input end of the rectification filter module is connected with a mains supply, the output end of the rectification filter module is connected with the input end of the voltage output module, the boosting dimming constant current module is connected with the voltage output module, the output end of the voltage output module is connected with the voltage stabilizing control module, the voltage stabilizing output module controls the boosting dimming constant current module through a PWM signal, and the voltage stabilizing control module is connected with a load.
2. A dimming circuit capable of stabilizing an output voltage according to claim 1, the voltage stabilization control module comprises a chip U2, a power supply pin of the chip U2 is connected with a module power supply voltage, the voltage detection end of the chip U2 is connected with one end of a resistor R4 and one end of a resistor R5, the other end of the resistor R4 is connected with the output end of the voltage output module and connected with the load input end, the other end of the resistor R5 is connected with the source of the MOS transistor Q2 and grounded, the drain of the MOS transistor Q2 is connected with the output end of the load, the grid of the MOS transistor Q2 is connected with one end of the resistor R6 and one end of a capacitor C4, the other end of the capacitor C4 is grounded, the MOS transistor Q2 stabilizes output voltage by adjusting voltage drop between the drain and the source, the other end of the resistor R6 is connected with a first signal output end of the chip U2, and a second signal output end of the chip U2 outputs PWM signals to the chip U1.
3. A dimming circuit as claimed in claim 2, wherein the chip U2 is a wireless rf control module.
4. A dimming circuit as claimed in claim 1, wherein the voltage output module comprises an electrolytic capacitor C3, the anode of the electrolytic capacitor C3 is connected to the cathode of the diode D1 and to the other end of the resistor R4, the cathode of the electrolytic capacitor C3 is connected to the other end of the resistor R5 and to ground, the anode of the diode D1 is connected to one end of the inductor L2A and to the drain of the MOS transistor Q1, and the other end of the inductor L2A is connected to the output terminal of the rectifying and filtering circuit.
5. A dimming circuit capable of stabilizing an output voltage according to claim 1, the boosting dimming constant current module comprises a chip U1, wherein a driving end of the chip U1 is connected with a gate of a MOS transistor Q1, a drain of the MOS transistor Q1 is connected with an anode of a diode D1, a source of the MOS transistor Q1 is connected with a current detection end of a chip U1 and is grounded through a resistor R3, the other end of a secondary side inductor L2B is connected with an anode of a diode D2 and is grounded, one end of the secondary side inductor L2B is connected with a cathode of a diode D2, an anode of the diode D3 and one end of a resistor R1, a cathode of the diode D3 is connected with one end of a capacitor C5 and is connected with a voltage input end of the chip U1, the other end of the resistor R1 is connected with one end of a resistor R2 and is connected with a feedback end of the chip U1, a compensation end of the chip U1 is grounded through a capacitor C6, and a ground end of a ground terminal of the chip U1 is connected with the other end of the capacitor C5 and the resistor R2.
6. A dimming circuit as claimed in claim 1, wherein the rectifying-filtering module comprises a filtering unit and a rectifying unit, the input terminal of the filtering unit is connected to the mains supply, the output terminal of the filtering unit is connected to the input terminal of the rectifying unit, the output terminal of the rectifying unit is connected to one end of a capacitor C7 and to the input terminal of the voltage output module, and the other end of the capacitor C7 is grounded.
7. A dimming circuit as claimed in claim 1, wherein the load is a LED string, the input end of the LED string is connected to the other end of the resistor R4, and the output end of the LED string is connected to the drain of the MOS transistor Q2.
8. A dimming circuit as claimed in claim 1, wherein the dimming circuit further comprises a circuit protection unit connected between the input terminal of the rectifying and filtering circuit and the mains input.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110638065.9A CN113329543A (en) | 2021-06-08 | 2021-06-08 | Dimming circuit capable of stabilizing output voltage |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110638065.9A CN113329543A (en) | 2021-06-08 | 2021-06-08 | Dimming circuit capable of stabilizing output voltage |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113329543A true CN113329543A (en) | 2021-08-31 |
Family
ID=77420399
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110638065.9A Pending CN113329543A (en) | 2021-06-08 | 2021-06-08 | Dimming circuit capable of stabilizing output voltage |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113329543A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114173460A (en) * | 2021-11-19 | 2022-03-11 | 深圳市多思迈光电有限公司 | Lamp control circuit and controller |
-
2021
- 2021-06-08 CN CN202110638065.9A patent/CN113329543A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114173460A (en) * | 2021-11-19 | 2022-03-11 | 深圳市多思迈光电有限公司 | Lamp control circuit and controller |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102364991B (en) | Switching power supply controller for constant current driving of LED by primary side control and method for constant current driving of LED | |
| RU2560835C2 (en) | Adaptive circuit | |
| CN105337485B (en) | Circuit of power factor correction, LED driving circuit and lighting apparatus | |
| CN102202449A (en) | LED driving control circuit and method | |
| US10834793B2 (en) | Power supply circuit and LED driving circuit | |
| US9997996B1 (en) | Power converter system and method for operating a power converter system | |
| CN102612196B (en) | LED (Light Emitting Diode) constant-current drive circuit and LED lamp using same | |
| CN110808681A (en) | Passive PFC resonant converter and control method thereof | |
| CN215453343U (en) | Dimming circuit capable of stabilizing output voltage | |
| CN113329543A (en) | Dimming circuit capable of stabilizing output voltage | |
| CN102611316A (en) | Flyback converter controlled constant-current output circuit and method | |
| CN215073040U (en) | LED lamp lighting system and dimmer and LED lamp that contain thereof | |
| US8304996B2 (en) | Photosensor circuits including a current amplifier | |
| CN212210864U (en) | Ammeter power supply circuit and ammeter | |
| CN102781147B (en) | LED (Light-emitting diode) power supply circuit with high power factor | |
| CN105101539A (en) | Light-emitting diode (LED) constant current driving circuit | |
| TWI448191B (en) | Feedback control to reduce power consumption light-emitting diode driving device | |
| CN210093612U (en) | LED double-color dimming built-in power supply | |
| US20220302732A1 (en) | Charging circuit and charging device | |
| CN207099392U (en) | Power supply circuit and apply its LED drive circuit | |
| CN102612195B (en) | LED (light emitting diode) constant current driving circuit and LED lamp using same | |
| CN202841608U (en) | LED power supply circuit possessing high power factor | |
| CN210469809U (en) | Driver | |
| CN110099476B (en) | High-integration-level high-PF intelligent dimming circuit structure | |
| CN210297569U (en) | Wide-range input-output AC-DC converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |