LED lamp dimming control circuit

Abstract

The utility model provides a dimming control circuit for an LED lamp. The dimming control circuit comprises a current regulation and control module, a dimming chip, a driving module, a main lighting unit and an auxiliary lighting unit, the input end of the current regulation and control module is connected with the first output end of the dimming chip, and the output end of the current regulation and control module is connected with the current sampling end of the driving module; the output end of the driving module is connected with the current end of the dimming chip; the first output end of the dimming chip is connected with the output end of the main lighting unit, and the second output end of the dimming chip is connected with the auxiliary lighting unit; the switch detection end of the dimming chip is used for detecting the power switch state and gating the first output end or the second output end according to the power switch state. The current regulation and control module is used for regulating the output current of the driving module according to the gating mode of the dimming chip, so that the dimming function of the main lighting unit and the auxiliary lighting unit is realized by regulating the current, and the circuit design cost can be reduced while the circuit is simplified.

Description

Technical Field

[0001] The utility model relates to the technical field of equipment failure prediction, in particular to an LED lamp dimming control circuit. Background Art

[0002] Currently, most LED dimming lamps use intelligent modules with communication capabilities, such as microcontrollers, 2.4G, or WiFi, to control the brightness of the LED lamp. This means that dimming requires the coordination of hardware and software. However, these intelligent modules themselves require dedicated power supplies, which complicates the lamp circuitry and increases costs. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a LED lamp dimming control circuit, simplify circuit design and reduce costs.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A dimming control circuit for an LED lamp comprises a current control module, a dimming chip, a driving module, a main lighting unit and a secondary lighting unit; the input end of the current control module is connected to the first output end of the dimming chip, and the output end of the current control module is connected to the current sampling end of the driving module; the output end of the driving module is connected to the current end of the dimming chip; the first output end of the dimming chip is connected to the output end of the main lighting unit, and the second output end of the dimming chip is connected to the secondary lighting unit; the switch detection end of the dimming chip is used to detect the power switch state and select the first output end or the second output end according to the power switch state.

[0006] Furthermore, the current control module includes an optocoupler, a first resistor and a MOS tube; the detection end of the optocoupler is connected to the first output end of the dimming chip, the first output end of the optocoupler is connected to one end of the first resistor and the gate of the MOS tube, and the second output end of the optocoupler is connected to the source of the MOS tube; the other end of the first resistor is connected to the power supply; the drain of the MOS tube is connected to the current sampling end of the driving module.

[0007] Furthermore, the current control module also includes a voltage regulator tube; the positive electrode of the voltage regulator tube is respectively connected to the first output end of the optocoupler, one end of the first resistor and the gate of the MOS tube; the negative electrode of the voltage regulator tube is respectively connected to the second output end of the optocoupler and the source of the MOS tube.

[0008] Furthermore, the current control module also includes a first capacitor; one end of the first capacitor is respectively connected to the first output end of the optocoupler, one end of the first resistor and the gate of the MOS tube; the other end of the first capacitor is respectively connected to the second output end of the optocoupler and the source of the MOS tube.

[0009] Furthermore, the dimming chip includes a wall-cut two-speed dimming chip, and the peripheral circuit includes a second resistor; the first output pin of the wall-cut two-speed dimming chip is connected to the output end of the main lighting unit; the second output pin of the wall-cut two-speed dimming chip is connected to the auxiliary lighting unit; the clock pin of the wall-cut two-speed dimming chip is connected to the second resistor, and the other end of the second resistor is used to be connected to the power supply; the current pin of the wall-cut two-speed dimming chip is connected to the output end of the driving module.

[0010] Furthermore, the driving module includes a constant current control chip, a diode, an inductor and a filter capacitor; the drain output end of the constant current control chip is respectively connected to the positive pole of the diode and one end of the inductor; the other end of the inductor is respectively connected to the negative pole of the filter capacitor and the current end of the dimming chip; the current sampling end of the constant current control chip is connected to the output end of the current control module; the power supply end of the constant current control chip, the negative pole of the diode and the positive pole of the filter capacitor are all connected to the power supply.

[0011] Furthermore, the constant current control chip includes a step-down chip, a buck-boost chip, a boost chip or a linear chip.

[0012] Furthermore, the driving module also includes a third resistor and a fourth resistor; the current sampling end of the constant current control chip is respectively connected to one end of the third resistor and one end of the fourth resistor; the other end of the third resistor is grounded; and the other end of the fourth resistor is connected to the output end of the current control module.

[0013] Furthermore, it also includes a rectifier module; the input end of the rectifier module is used to connect to the power supply, and the output end of the rectifier module is respectively connected to the power supply end of the dimming chip, the power supply end of the driving module, the input end of the main lighting unit and the input end of the auxiliary lighting unit.

[0014] Furthermore, a fuse resistor is included; one end of the fuse resistor is connected to the power supply, and the other end is connected to the input end of the rectifier module.

[0015] The beneficial effect of the present invention is that: the current control module, the dimming chip and the driving module are connected, and after the main lighting unit and the auxiliary lighting unit are selected by detecting the power switch status through the dimming chip, the current control module adjusts the output current of the driving module according to the selection mode of the dimming chip, thereby realizing the function of dimming the main lighting unit and the auxiliary lighting unit by adjusting the current. Compared with the existing dimming control function realized by a single-chip microcomputer or other intelligent modules, it can simplify the circuit while reducing the circuit design cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a circuit diagram of an LED lamp dimming control circuit in an embodiment of the present utility model;

[0017] Description of labels:

[0018] 1. Current control module; 2. Drive module; LED1, main lighting unit; LED2, auxiliary lighting unit; 3. Rectifier module; IC2, dimming chip; BR1, rectifier bridge stack; F1, fuse resistor; U1, optocoupler; R1, first resistor; Q1, MOS tube; ZD1, voltage regulator tube; C1, first capacitor; R2, second resistor; IC1, constant current control chip; D1, diode; L1, inductor; E1, filter capacitor; R3, third resistor; R4, fourth resistor. DETAILED DESCRIPTION

[0019] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following description is given in conjunction with the embodiments and the accompanying drawings.

[0020] Please refer to Figure 1 , a LED lamp dimming control circuit, including a current control module, a dimming chip, a driving module, a main lighting unit and a secondary lighting unit; the input end of the current control module is connected to the first output end of the dimming chip, and the output end of the current control module is connected to the current sampling end of the driving module; the output end of the driving module is connected to the current end of the dimming chip; the first output end of the dimming chip is connected to the output end of the main lighting unit, and the second output end of the dimming chip is connected to the secondary lighting unit; the switch detection end of the dimming chip is used to detect the power switch state, and select the first output end or the second output end according to the power switch state.

[0021] From the above description, it can be seen that the beneficial effect of the present invention is that: the current control module, the dimming chip and the driving module are connected, and after the main lighting unit and the auxiliary lighting unit are selected by detecting the power switch status through the dimming chip, the current control module adjusts the output current of the driving module according to the selection mode of the dimming chip, thereby realizing the function of dimming the main lighting unit and the auxiliary lighting unit by adjusting the current. Compared with the existing dimming control function realized by a single-chip microcomputer or other intelligent modules, it simplifies unnecessary communication functions and focuses on realizing the dimming function; it can reduce the circuit design cost while simplifying the circuit.

[0022] Furthermore, the current control module includes an optocoupler, a first resistor and a MOS tube; the detection end of the optocoupler is connected to the first output end of the dimming chip, the first output end of the optocoupler is connected to one end of the first resistor and the gate of the MOS tube, and the second output end of the optocoupler is connected to the source of the MOS tube; the other end of the first resistor is connected to the power supply; the drain of the MOS tube is connected to the current sampling end of the driving module.

[0023] From the above description, it can be seen that after the optocoupler detects the strobe state of the dimming chip, it can control the MOS tube to be turned on or off, thereby adjusting the current sampling end signal of the driver module, and then adjusting the output current of the driver module; at the same time, the optocoupler has a good isolation effect on the input / output electrical signals, which can improve the accuracy of MOS tube state control.

[0024] Furthermore, the current control module also includes a voltage regulator tube; the positive electrode of the voltage regulator tube is respectively connected to the first output end of the optocoupler, one end of the first resistor and the gate of the MOS tube; the negative electrode of the voltage regulator tube is respectively connected to the second output end of the optocoupler and the source of the MOS tube.

[0025] It can be seen from the above description that by providing a voltage regulator tube, a relatively stable voltage can be provided for the MOS tube, so that the MOS tube can operate stably.

[0026] Furthermore, the current control module also includes a first capacitor; one end of the first capacitor is respectively connected to the first output end of the optocoupler, one end of the first resistor and the gate of the MOS tube; the other end of the first capacitor is respectively connected to the second output end of the optocoupler and the source of the MOS tube.

[0027] It can be seen from the above description that by providing the first capacitor, interference to the current control module can be eliminated.

[0028] Furthermore, the dimming chip includes a wall-cut two-speed dimming chip, and its peripheral circuit includes a second resistor; the first output pin of the wall-cut two-speed dimming chip is connected to the output end of the main lighting unit; the second output pin of the wall-cut two-speed dimming chip is connected to the auxiliary lighting unit; the clock pin of the wall-cut two-speed dimming chip is connected to the second resistor, and the other end of the second resistor is used to be connected to the power supply; the current pin of the wall-cut two-speed dimming chip is connected to the output end of the driving module.

[0029] From the above description, it can be seen that a two-speed wall-cut dimming chip is used as the control chip of the dimming module, and after detecting the power switch state based on the second resistor, the internal conduction path is switched to realize the switching of the main lighting unit and the auxiliary lighting unit.

[0030] Furthermore, the driving module includes a constant current control chip, a diode, an inductor and a filter capacitor; the drain output end of the constant current control chip is respectively connected to the positive pole of the diode and one end of the inductor; the other end of the inductor is respectively connected to the negative pole of the filter capacitor and the current end of the dimming chip; the current sampling end of the constant current control chip is connected to the output end of the current control module; the power supply end of the constant current control chip, the negative pole of the diode and the positive pole of the filter capacitor are all connected to the power supply.

[0031] From the above description, it can be seen that the driving module composed of a constant current control chip, a diode, an inductor and a filter capacitor can realize the control of the sampling current while providing the corresponding operating voltage for the main lighting unit and the auxiliary lighting unit.

[0032] Furthermore, the constant current control chip includes a step-down chip, a buck-boost chip, a boost chip or a linear chip.

[0033] As can be seen from the above description, the constant current control chip can adopt a buck chip, a buck-boost chip, a boost chip or a linear chip, so that the circuit can be applied to different lighting application scenarios.

[0034] Furthermore, the driving module also includes a third resistor and a fourth resistor; the current sampling end of the constant current control chip is respectively connected to one end of the third resistor and one end of the fourth resistor; the other end of the third resistor is grounded; and the other end of the fourth resistor is connected to the output end of the current control module.

[0035] From the above description, it can be seen that by setting the third resistor and the fourth resistor and connecting the fourth resistor to the current control module, that is, when the current control module is turned on, the third resistor and the fourth resistor can work at the same time, thereby increasing the output current of the driving module; and when the current control module is turned off, the third resistor works alone to reduce the output current of the driving module.

[0036] Furthermore, it also includes a rectifier module; the input end of the rectifier module is used to connect to the power supply, and the output end of the rectifier module is respectively connected to the power supply end of the dimming chip, the power supply end of the driving module, the input end of the main lighting unit and the input end of the auxiliary lighting unit.

[0037] As can be seen from the above description, the input AC power is converted into DC power by providing a rectifier module.

[0038] Furthermore, a fuse resistor is included; one end of the fuse resistor is connected to the power supply, and the other end is connected to the input end of the rectifier module.

[0039] As can be seen from the above description, by providing a fuse resistor at the input end of the rectifier module, the circuit is protected by melting the fuse resistor when an abnormality occurs in the circuit.

[0040] The LED lamp dimming control circuit provided by the utility model can be applied to different lighting scenarios, and the following is an explanation through specific implementation methods:

[0041] Example 1

[0042] Please refer to Figure 1 A LED lamp dimming control circuit includes a current control module 1, a dimming chip IC2, a driver module 2, a main lighting unit LED1, a secondary lighting unit LED2, and a rectifier module 3; the input end of the current control module 1 is connected to the first output end of the dimming chip IC2, the output end of the current control module 1 is connected to the current sampling end of the driver module 2; the output end of the driver module 2 is connected to the current end of the dimming chip IC2; the first output end of the dimming chip IC2 is connected to the output end of the main lighting unit LED1, and the second output end of the dimming chip IC2 is connected to the secondary lighting unit LED2; The switch detection end of the dimming chip IC2 is used to detect the power switch state and select the first output end or the second output end according to the power switch state; the input end of the rectifier module 3 is used to connect to the power supply, and the output end of the rectifier module 3 is respectively connected to the power supply end of the dimming chip IC2, the power supply end of the driving module 2, the input end of the main lighting unit LED1 and the input end of the auxiliary lighting unit LED2; wherein, the rectifier module 3 is a rectifier bridge stack BR1, and the input end of the rectifier bridge stack BR1 is also provided with a fuse resistor F1, one end of the fuse resistor F1 is connected to the power supply, and the other end is connected to the input end of the rectifier module 3.

[0043] Among them, the current control module 1 includes an optocoupler U1, a first resistor R1, a MOS tube Q1, a voltage regulator ZD1 and a first capacitor C1; the detection end (U1A) of the optocoupler U1 is connected to the first output end (D1) of the dimming chip IC2, the first output end of the optocoupler U1 is respectively connected to one end of the first resistor R1, the gate of the MOS tube Q1, one end of the first capacitor C1 and the positive electrode of the voltage regulator ZD1, the second output end of the optocoupler U1 is respectively connected to the source of the MOS tube Q1, the negative electrode of the voltage regulator ZD1 and the other end of the first capacitor C1, and is grounded. ; The other end of the first resistor R1 is connected to the output end of the rectifier module 3; the drain of the MOS tube Q1 is connected to the current sampling end (CS) of the driving module 2; wherein, the detection end (U1A) of the optocoupler U1 is further provided with a resistor R8, a resistor R9 and a diode D2, the cathode of the diode D2 is connected to the first output end (D1) of the dimming chip IC2, the anode of the diode D2 is connected to the resistor R8 and the resistor R9 respectively, the other end of the resistor R8 is connected to the output end of the rectifier module 3, and the other end of the resistor R9 is connected to the detection end (U1A) of the optocoupler U1.

[0044] The dimming chip IC2 includes a wall-cut two-speed dimming chip IC2, and the peripheral circuit includes a second resistor R2; the first output pin (D1) of the wall-cut two-speed dimming chip IC2 is connected to the output end of the main lighting unit LED1; the second output pin (D2) of the wall-cut two-speed dimming chip IC2 is connected to the auxiliary lighting unit LED2; the clock pin (CLK) of the wall-cut two-speed dimming chip IC2 is connected to the second resistor R2, and the other end of the second resistor R2 is used to be connected to the live wire input end; the current pin (VDD) of the wall-cut two-speed dimming chip IC2 is connected to the output end of the driving module 2; wherein,

[0045] The driving module 2 includes a constant current control chip IC1, a diode D1, an inductor L1, a filter capacitor E1, a third resistor R3 and a fourth resistor R4; wherein the constant current control chip IC1 includes a variety of driving control schemes such as a buck chip (BUCK), a buck-boost chip (Buck-Boost), a boost chip (Boost) or a linear chip; the drain output terminal (Drain) of the constant current control chip IC1 is respectively connected to the positive electrode of the diode D1 and one end of the inductor L1; the other end of the inductor L1 is respectively connected to the negative electrode of the filter capacitor E1 and the current terminal of the dimming chip IC2; the power supply terminal (HV) of the constant current control chip IC1, the negative electrode of the diode D1 and the positive electrode of the filter capacitor E1 are all connected to the power supply; the current sampling terminal (CS) of the constant current control chip IC1 is respectively connected to one end of the third resistor R3 and one end of the fourth resistor R4; the other end of the third resistor R3 is grounded; the other end of the fourth resistor R4 is connected to the output terminal (CS) of the current control module 1, that is, connected to the drain of the MOS tube Q1.

[0046] The specific working principle of the above LED lamp dimming control circuit is as follows:

[0047] When the system is powered on, the bus voltage (L&N) supplies power to the constant current control chip IC1. The constant current control circuit, mainly composed of the constant current control chip IC1, freewheeling diode D1, power inductor L1, and output filter capacitor E1, starts to work, thereby driving the subsequent load; the bus voltage also supplies power to the dimming chip IC2 through the resistor R6, so that the dimming chip IC2 starts to work; the dimming chip IC2 detects the switching state of the input end through the CLK pin and the second resistor R2, thereby realizing the control of the two LED lights.

[0048] When the input switch is turned on for the first time, the logic of the dimming chip IC2 causes the D1 pin to be connected to the GND pin, and the main lighting unit LED1 is lit. The LED output current flows through the resistor R8, the diode D2, and then the D1 pin to the ground, so that no current flows through the resistor R9 and the optocoupler U1 is non-conductive. The bus voltage drives the MOS tube Q1 to conduct through the first resistor R1, so that the fourth resistor R4 is grounded through the MOS tube Q1, thereby controlling the output current to increase, making the main lighting unit LED1 in a high-brightness state, suitable for conventional main lighting.

[0049] When the input switch is turned on again after being turned off, the chip logic disconnects pin D1 from pin GND, turning off the main lighting unit LED1. Pin D2 of dimming chip IC2 is connected to pin GND, lighting the auxiliary lighting unit LED2. The LED output current flows through resistors R8 and R9, turning on optocoupler U1. This, in turn, connects the gate of MOS transistor Q1 to ground through optocoupler U1, turning off MOS transistor Q1. The fourth resistor R4 is disconnected from ground, allowing the third resistor to operate independently, thereby reducing the output current and dimming the auxiliary lighting unit LED2 to a low brightness state, suitable for night lighting. This embodiment directly detects the state of channel D1 of the wall-cut chip to control the on / off of optocoupler U1, eliminating the need for external transistors and peripheral components, resulting in a simple and efficient circuit.

[0050] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent transformations made using the contents of the description and drawings of the present invention, or directly or indirectly applied in the relevant technical field, are also included in the patent protection scope of the present invention.

Claims

1. A LED lamp dimming control circuit, characterized in that: Including current control module, dimming chip, driver module, main lighting unit and auxiliary lighting unit; The input end of the current control module is connected to the first output end of the dimming chip, and the output end of the current control module is connected to the current sampling end of the driving module; The output end of the driving module is connected to the current end of the dimming chip; The first output end of the dimming chip is connected to the output end of the main lighting unit, and the second output end of the dimming chip is connected to the auxiliary lighting unit; the switch detection end of the dimming chip is used to detect the power switch state and select the first output end or the second output end according to the power switch state.

2. The LED lamp dimming control circuit according to claim 1, characterized in that: The current control module includes an optical coupler, a first resistor and a MOS tube; The detection end of the optocoupler is connected to the first output end of the dimming chip, the first output end of the optocoupler is connected to one end of the first resistor and the gate of the MOS tube, and the second output end of the optocoupler is connected to the source of the MOS tube; The other end of the first resistor is connected to a power supply; The drain of the MOS tube is connected to the current sampling terminal of the driving module.

3. The LED lamp dimming control circuit according to claim 2, characterized in that: The current control module also includes a voltage regulator tube; The positive electrode of the voltage regulator tube is respectively connected to the first output end of the optocoupler, one end of the first resistor and the gate of the MOS tube; The cathode of the voltage regulator tube is connected to the second output terminal of the optocoupler and the source of the MOS tube respectively.

4. The LED lamp dimming control circuit according to claim 2, characterized in that: The current control module further includes a first capacitor; One end of the first capacitor is connected to the first output end of the optocoupler, one end of the first resistor, and the gate of the MOS transistor respectively; The other end of the first capacitor is connected to the second output end of the optocoupler and the source of the MOS tube respectively.

5. The LED lamp dimming control circuit according to claim 1, characterized in that: The dimming chip includes a wall-cut two-speed dimming chip, and the peripheral circuit includes a second resistor; The first output pin of the wall-cut two-speed dimming chip is connected to the output end of the main lighting unit; The second output pin of the wall-cut two-speed dimming chip is connected to the auxiliary lighting unit; The clock pin of the wall-cut two-speed dimming chip is connected to the second resistor, and the other end of the second resistor is used to be connected to the power supply; The current pin of the wall-cut two-speed dimming chip is connected to the output end of the driving module.

6. The LED lamp dimming control circuit according to claim 1, characterized in that: The driving module includes a constant current control chip, a diode, an inductor and a filter capacitor; The drain output end of the constant current control chip is connected to the anode of the diode and one end of the inductor respectively; The other end of the inductor is connected to the negative electrode of the filter capacitor and the current end of the dimming chip respectively; The current sampling terminal of the constant current control chip is connected to the output terminal of the current control module; The power supply end of the constant current control chip, the cathode of the diode and the anode of the filter capacitor are all connected to the power supply.

7. The LED lamp dimming control circuit according to claim 6, characterized in that: The constant current control chip includes a step-down chip, a buck-boost chip, a boost chip or a linear chip.

8. The LED lamp dimming control circuit according to claim 6, characterized in that: The driving module further includes a third resistor and a fourth resistor; The current sampling terminal of the constant current control chip is connected to one end of the third resistor and one end of the fourth resistor respectively; The other end of the third resistor is grounded; The other end of the fourth resistor is connected to the output end of the current control module.

9. The LED lamp dimming control circuit according to claim 1, characterized in that: Also includes a rectifier module; The input end of the rectifier module is used to connect to the power supply, and the output end of the rectifier module is respectively connected to the power supply end of the dimming chip, the power supply end of the driving module, the input end of the main lighting unit and the input end of the auxiliary lighting unit.

10. The LED lamp dimming control circuit according to claim 9, characterized in that: Also includes a fuse resistor; One end of the fuse resistor is connected to the power supply, and the other end is connected to the input end of the rectifier module.

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