WO2013067761A1

WO2013067761A1 - Driving and controlling circuit for illumination of led

Info

Publication number: WO2013067761A1
Application number: PCT/CN2012/001441
Authority: WO
Inventors: 金德奎
Original assignee: Jin Dekui
Priority date: 2011-11-11
Filing date: 2012-10-26
Publication date: 2013-05-16

Abstract

The invention relates to a driving and controlling circuit for illumination of LED. It comprises an LED load with a constant-current driving circuit, a switching power-taking unit, and a control unit, wherein one end of the switching power-taking unit is connected with one end of the LED load, and the other end of the switching power-taking unit is connected with one end of a direct-current power supply, the other end of the direct-current power supply is connected with the other end of the LED load, the power output end of the switching power-taking unit is connected with the power input end of the control unit, and the signal output end of the control unit is connected with the signal input end of the switching power-taking unit. The present invention solves the problem of that the conventional driving and controlling circuit for illumination of the LED can not be used directly on the conventional laid two-wire system illuminating line, solves the radiation problem of the LED load, controls the starting or the stopping of the LED load, carries out the PWM dimming control on the load. The use is more convenient, the LED load works reliably and stably, and the popularization of the illumination of the LED under the existing condition is promoted.

Description

LED lighting drive control circuit

Technical field

[0001] The present invention relates to a control circuit, and more particularly to an LED illumination drive control circuit.

[0002] The existing LED lighting drive control circuit is usually disposed in the LED load, as shown in FIG. 1, including the AC/DC conversion circuit and the drive circuit, and the LED load is turned on and off by an external switch. . The heat generated by the AC/DC converter circuit and the driver circuit is superimposed on the heat generated by the LED device itself, especially the LED

Book

Bulbs and LED fluorescent lamps, although similar in shape to traditional incandescent lamps and fluorescent lamps, are favored by the public with a sense of tradition, but the limited space is packed with various parts, and the heat cannot be effectively dissipated in time. The increase has accelerated the light decay of LEDs and the longevity, which has become a major obstacle to the popularity of LEDs.

[0003] There are two types of dimmable LED drive control circuits, one is thyristor AC chopper dimming, and the other is PWM dimming.

[0004] The thyristor AC chopper dimming is formed by connecting a dimmer to an LED load in series with an AC power supply. As shown in FIG. 2, an AC/matching with the dimmer is installed in the LED load. The DC conversion circuit and the drive circuit change the chopping angle of the output AC by rotating the dimmer knob, and the LED load current is controlled by the AC/DC conversion circuit and the drive circuit of the LED load to extract the changed chop angle information. The advantage of the thyristor AC chopper dimming mode is that the wall dimmer can directly control the opening and closing of the LED load and dimming directly, eliminating the trouble of rewiring and the resulting cost. Improve, but in actual use, there will be problems such as poor matching of AC/DC conversion drive circuit and dimmer parameters or LED flicker caused by grid interference, low efficiency and power factor, and the same heat dissipation problem as above.

[0005] PWM dimming is usually connected by the PWM signal output end of the control circuit to the gate of the FET, the drain of the FET is connected to the negative pole of the LED load, and the source and the ground of the control circuit are connected to the common ground. The LED load positive pole is connected to the positive pole of the DC constant current output terminal of the AC/DC driving power supply, and the power input end of the control circuit is connected with the Vdd of the AC/DC driving power supply, as shown in FIG. A control circuit generates a PM signal with an adjustable duty cycle to the FET gate, and a correspondingly varying on-off response is generated across the MOSFET drain and source to drive the LED load dimming. This dimming method solves the defect of thyristor AC chopper dimming, high dimming precision, stable and reliable. It can be seen from Figure 3 that the connection characteristics of this circuit and the wiring mode of multiple lines determine that it cannot Direct sheds on existing two-wire lighting lines have to be re-routed, and ifcit has become inconvenient to use and an increase in the cost of use. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide an LED lighting driving control circuit and a control method thereof, which solve the problem that the existing LED lighting driving control circuit cannot be directly used on the existing already laid lighting circuit, and solve the LED problem. The heat dissipation problem of the load can control the LED load to be turned on or off, and can also perform P-dimming control on the load, so that the LED load can work reliably and stably, and promote the popularization of LED lighting under the existing conditions.

An LED lighting control circuit according to the above object of the invention includes an LED load having a constant current driving circuit, characterized in that:

[0008] A switch and power take-off unit (hereinafter referred to as a switch power take-off unit) and a control unit are included.

[0009] One end of the switch power take-off unit is connected to one end of the LED load, the other end of the switch power take-off unit is connected to one end of the DC power source, and the other end of the DC power source is connected to the other end of the LED load, and the switch is powered The power output end of the unit is connected to the power input end of the control unit, and the signal output end of the control unit is connected to the signal input end of the switch power take-off unit.

[0010] In one embodiment, the switch power take-off unit includes at least one field effect transistor, and a diode, an electrolytic capacitor, and a voltage stabilizing circuit.

[001 1] The drain of the FET is connected as one end of the switch power take-off unit to the negative pole of the LED load, and the source of the FET is used as the other end of the switch power take-off unit and connected to the negative pole of the DC power source, the field effect transistor The gate is connected to the signal output of the control unit or via a resistor to the signal output of the control unit. The positive pole of the LED load is connected to the positive pole of the DC power supply.

[0012] The anode of the diode is connected to the drain of the field effect transistor, the cathode of the diode is connected to the anode of the electrolytic capacitor and the input end of the voltage stabilizing circuit, and the output end of the voltage stabilizing circuit and the power input of the control unit The terminal connection, the source of the FET, the cathode of the electrolytic capacitor, the ground of the voltage stabilizing circuit, and the ground of the control unit are connected to the common ground.

[0013] In another aspect of the above embodiment, the drain of the FET is connected as one end of the switch power take-off unit to the negative pole of the LED load, and the source of the FET is used as the other end of the switch power take-off unit. The negative pole connection of the DC power source is connected to the anode of the DC power source by the drain of the FET as the switch power take-off unit, and the source of the FET is used as the anode of the switch power take-off unit instead of the anode of the LED load. .

[0014] In another embodiment, the switch power take-off unit includes at least one field effect transistor, a first resistor, a second resistor, a third resistor, a triode, and a diode, an electrolytic capacitor, and a voltage stabilizing circuit.

[0015] The drain of the FET is connected to the anode of the LED load as one end of the switch power take-off unit, and the source of the FET is connected to the anode of the DC power source as the other end of the switch power take-off unit, LED The negative pole of the load is connected to the negative pole of the DC power source, the gate of the FET is connected to one end of the first resistor, the other end of the first resistor is connected to the source of the FET, and one end of the second resistor is connected to the field. The gate of the effect tube is connected, the other end of the second resistor is connected to the collector of the transistor, the base of the transistor is connected to one end of the third resistor, and the other end of the third resistor is connected to the signal output end of the control unit. a cathode of the diode is connected to a drain of the field effect transistor, a positive pole of the electrolytic capacitor is connected to a source of the field effect transistor and an input end of the voltage stabilizing circuit, and an output end of the voltage stabilizing circuit and a power input end of the control unit The connection, the emitter of the triode, the anode of the diode, the cathode of the electrolytic capacitor, the ground of the voltage stabilizing circuit, and the ground of the control unit are connected to the common ground.

[0016] In another aspect of the above embodiment, the drain of the FET is connected to the anode of the LED load as one end of the switch power take-off unit, and the source of the FET is used as the switch power take-off unit. One end is connected to the positive pole of the direct current power source, the negative pole of the LED load is connected to the negative pole of the direct current power source, and the drain of the field effect transistor is connected as one end of the switch power take-off unit to the negative pole of the direct current power source, and the source of the field effect transistor is used as a switch. The other end of the power take-off unit is connected to the negative pole of the LED load, and the positive pole of the LED load is replaced with the positive pole of the DC power source.

[0017] In all of the above embodiments, a resistor is connected in parallel across the LED load.

[0018] The resistance of the resistor is calculated by R (U-Vc-Vd) /Is, U is the input voltage of the DC power supply, and Vc is the lowest voltage at the input end of the voltage regulator circuit to ensure normal operation, Vd is The tube voltage drop of the diode, Is is the sum of the maximum current consumed by the control unit and the regulator circuit and the current lost during operation.

[0019] In all of the above embodiments, the control unit comprises a microcontroller or an integrated circuit;

[0020] An information input module is further included, and the input mode is a button type or a touch type or an inductive type, and a signal output end of the information input module is connected to a signal input end of the microcontroller or the integrated circuit.

[0021] The sensing input mode of the information input module is an infrared sensing mode or a human body pyroelectric induction mode.

[0022] In all of the above embodiments, the control unit comprises a microcontroller or an integrated circuit;

[0023] The wireless or infrared remote control receiving circuit is further included, and the signal output end is connected to the signal input end of the microcontroller or the integrated circuit, and the power end is connected to the power output end of the voltage stabilizing circuit.

[0024] Since the driving control circuit of the present invention is connected in series with the LED load on the DC power supply, the problem that the existing LED lighting driving control circuit cannot be directly used on the existing two-wire lighting circuit has been solved, and the LED load is solved. The heat dissipation problem, |3⁄4 can control the LED load to be turned on or off, and can also perform PWM dimming control on the load, which is more convenient to use, and makes the LED load reliable and stable, and promotes the popularization of LED lighting under the existing conditions. DRAWINGS

1 is a block diagram showing the principle of a prior art LED bulb, fluorescent lamp and spotlight.

2 is a block diagram of a prior art thyristor chopper LED dimming principle.

3 is a block diagram of a prior art PWM LED dimming principle.

4 is a schematic block diagram of an embodiment of a positive pole of an LED-loaded positive pole-connected DC power supply according to the present invention.

5 is a schematic block diagram of an embodiment of a negative electrode of a LED-loaded negative-electrode DC power supply according to the present invention.

6 is a schematic diagram of a first embodiment of the N-channel of the field effect transistor of the present invention.

7 is a schematic diagram of a second embodiment of the NFET of the field effect transistor of the present invention.

8 is a schematic diagram of a first embodiment of a P-channel of the field effect transistor of the present invention.

9 is a schematic diagram of a second embodiment of the PFET of the present invention.

10 is a schematic diagram of the LED load of the present invention.

11 is a schematic diagram of an embodiment of the field effect transistor of the present invention having an N-channel multi-load.

12 is a schematic diagram of a P-channel multi-load embodiment of the field effect transistor of the present invention.

13 is a waveform diagram of a PWM signal, a D-S terminal voltage, a current take-off current, and a power take-off voltage when the LED load is turned off according to the present invention.

14 is a waveform diagram of a PWM signal, a D_S terminal voltage, a current take-off current, and a power take-off voltage when the LED load is turned on according to the present invention.

15 is a waveform diagram of a PWM signal, a voltage of a field effect transistor D-S terminal, a current drawn, and a power take-off voltage when the LED load is dimmed according to the present invention.

[0040] FIG. 16 is a flow chart of turning on and off the light of the present invention.

[0041] FIG. 17 is a dimming flow chart of the present invention. detailed description

[0042] The present invention will be further described below in conjunction with the drawings and embodiments.

[0043] An embodiment of the LED-loaded positive-electrode DC power supply positive electrode of the present invention is shown in FIG. 4, and includes an LED load 30 having a constant current driving circuit, a switch power take-off unit 20, and a control unit 10.

[0044] One end of the switch power take-off unit 20 is connected to the negative pole of the LED load 30, the other end of the switch power take-off unit 20 is connected to the negative pole of the DC power source, and the anode of the DC power source is connected to the anode of the LED load, and the switch power take-off unit The power output end of 20 is connected to the power input end of the control unit 10, and is controlled. The unit 10 is powered, and the signal output of the control unit 10 is connected to the signal input of the switch power take-off unit 20.

[0045] The LED load negative electrode power supply DC power supply negative electrode is implemented as shown in FIG. 5, which is different from the previous embodiment in that one end of the switch power take-off unit 20 is connected to the positive pole of the LED load 30, and the switch power take-off unit The other end of 20 is connected to the positive pole of the DC power supply, and the negative pole of the DC power supply is connected to the negative pole of the LED load.

The field effect transistor of the present invention is an N-channel first embodiment. As shown in FIG. 6, the switch power take-off unit 20 includes an N-channel field effect transistor Q21, a diode D21, an electrolytic capacitor C21, and a voltage stabilizing circuit IC21.

[0047] The drain D of the N-channel FET Q21 is connected as one end of the switch power take-off unit 20 to the negative pole of the LED load 30, and the source S of the N-channel FET Q21 is used as the other end of the switch power take-off unit 20 and DC. The anode of the power supply is connected, the gate G of the N-channel FET Q21 is connected to the signal output terminal P of the control unit 10 or connected to the signal output terminal of the control unit 10 through a resistor, and the anode of the LED load 30 and the anode of the DC power source connection.

[0048] The anode of the diode D21 is connected to the drain D of the field effect transistor Q21, the cathode of the diode D21 is connected to the anode of the electrolytic capacitor C21 and the input terminal Vin of the voltage regulator circuit IC21, and the output terminal Vout of the voltage regulator circuit IC21 and the control unit The power input terminal Vdd of 10 is connected, and the source S of the field effect transistor Q21, the cathode of the electrolytic capacitor C21, the ground GND of the voltage stabilizing circuit IC21, and the ground of the control unit 10 are connected to the common ground.

[0049] The field effect transistor of the present invention is an N-channel second embodiment, as shown in FIG. 7. Unlike the first embodiment of FIG. 6, the drain D of the N-channel FET Q21 serves as one end of the switch power take-off unit 20. The anode of the DC power source is connected, the source S of the N-channel FET Q21 is connected to the anode of the LED load 30 as the other end of the switch power take-off unit 20, and the cathode of the LED load 30 is connected to the cathode of the DC power source.

[0050] The field effect transistor of the present invention is a P-channel first embodiment. As shown in FIG. 8, the switch power take-off unit 20 includes a P-channel field effect transistor Q21, a first resistor R21, a second resistor R22, a third resistor R23, and a triode. Q22, and diode D21, electrolytic capacitor C21 and voltage regulator circuit IC21.

[0051] The drain D of the P-channel field effect transistor Q21 is connected as one end of the switch power take-off unit 20 to the anode of the LED load 30, and the source S of the P-channel field effect transistor Q21 is used as the other end of the switch power take-off unit 20. Connected to the positive pole of the DC power supply, the negative pole of the LED load 30 is connected to the negative pole of the DC power supply, the gate G of the P-channel FET Q21 is connected to one end of the first resistor R21, and the other end of the first resistor R21 is connected to the P-channel field effect. The source S of the transistor Q21 is connected, one end of the second resistor R22 is connected to the gate G of the P-channel field effect transistor Q21, the other end of the second resistor R22 is connected to the collector of the transistor Q22, and the base and the third of the transistor Q22 are connected. One end of the resistor R23 is connected, the other end of the third resistor R23 is connected to the signal output terminal P of the control unit 10, and the cathode of the diode D21 is connected to the drain D of the P-channel field effect transistor Q21, and electrolysis The anode of the capacitor C21 is connected to the source of the P-channel field effect transistor Q21 and the input terminal Vin of the voltage regulator circuit IC21. The output terminal Vout of the voltage regulator circuit IC21 is connected to the power input terminal Vdd of the control unit 10, and the emitter of the transistor Q22, The anode of the diode D21, the cathode of the electrolytic capacitor C21, the ground GND of the voltage stabilizing circuit IC21, and the ground of the control unit 10 are connected in common. The transistor Q22 in this embodiment can also be replaced with an N-channel field effect transistor.

[0052] The field effect transistor of the present invention is a P-channel second embodiment as shown in FIG. 9. Unlike the first embodiment of FIG. 8, the drain D of the P-channel field effect transistor Q21 serves as one end of the switch power take-off unit 20. The negative pole of the DC power source is connected, the source S of the P-channel FET Q21 is connected to the cathode of the LED load 30 as the other end of the switch power take-off unit 20, and the anode of the LED load 30 is connected to the anode of the DC power source.

[0053] The schematic diagram of the LED load 30 of the present invention is shown in FIG. 10, and a resistor R3U is connected in parallel across the LED load. The first purpose is to provide power to the switch power take-off unit 20 and the control unit 10 when the LED load 30 is turned off. It is a bypass shunt for the LED load, so that most of it flows through the resistor R31, and the current flowing through the LED load is extremely small, preventing the LED from flashing.

[0054] The resistance value R (U-Vc-Vd) /Is of the resistor R31D is the input voltage of the DC power supply, Vc is the lowest voltage at the input end of the voltage regulator circuit IC21 to ensure normal operation, and Vd is the voltage drop of the diode D21 tube. Is is the sum of the maximum current consumed by the control unit 10 and the voltage stabilizing circuit IC21 and the current lost during operation, and the capacitance loss such as the electrolytic capacitors C21 and C22 is negligible. For example, if Is is 700 μA, U=20V, Vc=5V, Vd=0. 7V, then (U-Vc-Vd) /Is: (20-5-0. 7) /0. 0007=20428. The loss of the energy consumption of the 6 Ω, R ^ 20ko resistance 20k in parallel with the LED load is only 0. 002W, if the LED load is calculated as 6W, only the loss of 0. 3 / 1000 during the LED load lighting, this The power savings from using the invention in the existing lines and rapidly replacing incandescent and energy-saving lamps is negligible. Moreover, in the case of multi-loop use, the resistance can be connected only in the main circuit LED load, and the LED load of the other circuits can be disabled, which neglects this and its small loss.

[0055] The control unit 10 includes a microcontroller or an integrated circuit, and further includes an information input module, and the input mode is a key input mode or a touch input mode or an inductive input mode, or any combination of the three modes. The signal output of the information input module is coupled to the signal input of the microcontroller or integrated circuit. Inductive use of infrared reflective or blocking sensing, this mode of operation is suitable for kitchens, bathrooms or public places. Human body pyroelectric induction can also be used, which is suitable for corridor use. In the case of a corridor similar to the need for emergency evacuation, the fire control line needs to be introduced to the control unit or the switch power take-off unit, so that the LED load is controlled by the fire control circuit or the switch power take-off unit when the emergency situation requires emergency evacuation. The luminaire forcibly turns on emergency lighting. [0056] The control unit 10 may further comprise a wireless or infrared remote control receiving circuit, the signal output end of which is connected to the signal input end of the microcontroller or the integrated circuit, and the power input end of which is connected to the power output end of the voltage stabilizing circuit IC21.

[0057] The field effect transistor of the present invention is an N-channel multi-load implementation, as shown in FIG. 11, and the signal output terminals P1, P2, and P3 of the control unit 10 are respectively connected to an N-channel FET Q21 that controls the LED load 31 circuit, and the control LED. The 32-loop N-channel FET Q22 and the gate of the N-channel FET Q23 controlling the LED load 33 loop, the LED load 32 and 33 loops save the diode for power take-off in the LED load 31 loop, which is stable Reliable work.

[0058] The above embodiment can also be split into three independent control circuits, which are respectively controlled by three control units for the respective FETs, and the ground ends are connected in common, which is used for the microcontroller or integrated circuit used by the control unit. A circuit with only one PWM signal output interface is effective.

[0059] The field effect transistor of the present invention is a P-channel multi-load implementation. As shown in FIG. 12, the signal output terminals P1, P2, and P3 of the control unit 10 are respectively connected to the transistor Q22 for controlling the LED load 31 circuit through the resistors R23, R26, and R29. The LED Q24 of the LED load 32 circuit and the base of the transistor Q26 which controls the LED load 33 circuit, the LED load 32 and 33 circuits save the diode for taking power in the circuit of the LED load 31, and can work stably and reliably.

[0060] The above embodiment can also be split into three independent control circuits, and the three FETs respectively control the respective FETs, which has only one PWM signal for the microcontroller or integrated circuit used by the control unit. The architecture of the output interface is also effective.

[0061] The control unit 10 can also set a communication interface that can receive operation and control information from the outside.

[0062] The control method and working principle of the invention:

[0063] The microcontroller MCU or the integrated circuit in the control unit detects the input operation information according to a certain period and generates a corresponding control signal according to the received light-on information or the light-off information to transmit the field effect in the switch power take-off unit. The FET receives the signal and responds to the switching action, driving the LED load to light or extinguish, and the FET and the diode and the electrolytic capacitor both take power and store energy during the light-on, and the generated power supply control unit works normally. .

[0064] FIG. 16 is a flow chart showing the turning on and off of the present invention, including the following steps:

[0065] Step S01, the microcontroller MCU or integrated circuit (hereinafter referred to as MCU) in the control unit detects the input information according to a certain period;

[0066] Step S02, the MCU determines whether the received light-on information is received, if the light-on information is not received, continues to detect, if the light-on information is received, go to step S03; [0067] Step S03, the MCU sends a PWM signal, and the duty ratio of the PWM signal is close to 100%, 95%, 96%, 97%, 98% or 99%, preferably 99%, sent to the field effect. tube;

[0068] Step S04, the FET receives the PWM signal and drives the LED load in response to the switching action;

[0069] Step S05, the LED load is lit;

[0070] Step S06, the MCU continues to detect the input information;

[0071] Step S07, determining whether the received light-off information is received, if not received, then proceeding to step 03, if yes, proceeding to step S08;

[0072] Step S08, the MCU stops transmitting the PWM signal;

[0073] Step S09, the FET does not receive the PWM signal, and the response is turned off;

[0074] Step S10, the LED negative sign |, off.

[0075] The method of taking power during turning on and off is as follows -

[0076] During the light-off period or initial power-on, the FET in the power-off unit of the switch is in an off state, and the current of the DC power source supplies power to the electrolytic capacitor and the voltage stabilizing circuit and the control unit through the LED load and the resistors at both ends of the load and the diode. , so that the control unit works normally, the waveform of each collection point is shown in Figure 13.

[0077] During the light-on period, when the PWM signal received by the FET is at a low level, the FET is turned off, the current of the DC power source is stored by the LED load and the resistor at both ends of the load, and the diode is used to store the energy to the electrolytic capacitor and to the voltage stabilizing circuit. And the control unit is powered. When the P signal received by the FET is at a high level, the FET is turned on, and the diode prevents the current from flowing backward through the FET into the common ground. The energy stored by the electrolytic capacitor continues to supply power to the voltage stabilizing circuit and the control unit. The waveform of each collection point is shown in Fig. 14. The control and power-taking method and principle of the present invention will be described with a PWM signal duty ratio of 99%.

[0078] The control method and working principle of the present invention further include:

[0079] The microcontroller MCU or the integrated circuit in the control unit detects the input operation information according to a certain period and generates a corresponding control signal according to the received dimming information or the dimming information to be transmitted to the field in the switch power take-off unit. The effect tube, the FET receives the signal and responds to the switching action, drives the LED load dimming, and the FET and the diode and the electrolytic capacitor together take the role of power taking and energy storage during the turning on, and the generated power supply control unit works normally.

[0080] FIG. 17 shows a dimming flowchart of the present invention, including the following steps:

[0081] Step S10, the microcontroller MCU or integrated circuit (hereinafter referred to as MCU) in the control unit detects the input information according to a certain period;

[0082] Step S12, the MCU determines whether the input dimming information is received, if the dimming information is not received, Continued detection, if receiving dimming information, go to step S13;

[0083] Step S13, the MCU sends a corresponding duty cycle signal to the FET;

[0084] Step S14, the FET receives the P-signal and responds to the switching action to drive the LED load;

[0085] Step S15, the LED load is illuminated according to the required brightness;

[0086] Step S16, the MCU continues to detect the input information;

[0087] Step S17, determining whether the received dimming information change information is received, if not received, then go to step 13, if received, go to step S18;

[0088] Step S18, the MCU sends a new PWM signal.

[0089] Step S19, the FET receives a new PWM signal, and responds to the new smashing action;

[0090] Step S20, the LED load emits light according to the adjusted brightness.

[0091] During the dimming operation, the principle of power taking is the same as that during the light-on period, except that the duty ratio of the PWM signal is different. The waveform of each collection point is as shown in FIG. 15 , and only the dimming duty ratio is 10%. The control and power take-off method and principle of the present invention.

[0092] It should be noted that the above steps, in conjunction with the flowcharts shown in FIG. 16 and FIG. 17, only describe the main technical features of the control method of the present invention, and the steps and flows thereof. The steps S01 to S10 and the steps S11 to S20 should be performed by the user. The actual operational information is interrelated and interspersed. If the actual operation occurs, the MCU detects the input dimming information after receiving the light-on information in step S02, so that it is necessary to respond to this information and proceed to step S13. If the MCU detects the turn-off information and makes a judgment after proceeding to step S20, it immediately responds to this message and proceeds to S08. The correlation and transformation between the specific procedures and the various steps in the actual operation and use are prior art and can be successfully completed by ordinary people in the field, and will not be described in detail herein.

[0093] The DC power input terminal of the present invention is connected to an AC/DC power adapter to convert AC AC to DC DC, and its output voltage is a safe voltage of 36V. In addition, the DC power input terminal can also be connected to an AC/DC circuit to directly convert AC220V or 110V AC to DC of the same voltage. This requires the LED load to be a high-voltage DC load. This method has higher conversion efficiency, but requires LED load. Higher, less secure than the former, therefore, the former is generally preferred. Since the AC/DC adapter can be used to output DC control of multiple loops of LED load, the output power is much larger than the built-in AC/DC converter in a single LED load. It is well known that the larger the AC/DC adapter power, the easier the efficiency is. High, therefore, the present invention can also improve the efficiency of LED lighting.

[0094] For the indoor application of the invention, the AC/DC converter can be installed in the switchboard or be wall mounted, and the live line L and the neutral line N of the original lighting line are in the switchboard and the lower end of the circuit breaker. Remove, connect the AC220V input of the AC/DC converter directly to the lower end of the circuit breaker, the DC output and the removed lighting line The fire line L of the road is connected with the zero line N, and the single fire line wall switch of each room is removed, directly replaced with the drive control switch with the circuit of the invention, and then the lamp is replaced by the LED load lamp of the invention. Realize the replacement of the original system of indoor LED lighting system.

[0095] The resistors in parallel with the LED load can be built in parallel with the LED load fixture or externally connected to the terminals of the line and the LED load fixture. For external resistors, small modules with leads or terminals can be used to make installation easier.

The constant current driving circuit in the LED load described in the present invention is a prior art, and only one of the constant current circuits is shown in FIG. 10. The present invention is also applicable to constant current circuits of other topologies. PWM frequency To select a frequency that is not noticeable and is not harmful to health, it is usually selected from 100 Hz to 1000 Hz, which is also within the scope of the prior art and is not specifically defined herein.

The above description is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept. It belongs to the scope of protection of the present invention.

Claims

Claim

1. An LED illumination drive control circuit comprising an LED load having a constant current drive circuit, the characteristic of which is:

The switch power take-off unit and the control unit are included;

One end of the switch power take-off unit is connected to one end of the LED load, the other end of the switch power take-off unit is connected to one end of the DC power source, and the other end of the DC power source is connected to the other end of the LED load, and the power of the switch power take-off unit is The output end is connected to the power input end of the control unit, and the signal output end of the control unit is connected to the signal input end of the switch power take-off unit.

2. The LED lighting drive control circuit according to claim 1, wherein:

The switch power take-off unit includes at least one field effect transistor, and a diode, an electrolytic capacitor, and a voltage stabilizing circuit. The drain of the FET is connected as a switch power take-off unit to the negative pole of the LED load, and the source of the FET The other end of the switch power take-off unit is connected to the negative pole of the DC power supply, and the gate of the FET is connected to the signal output end of the control unit or connected to the signal output end of the control unit through a resistor.

The anode of the LED load is connected to the anode of the DC power source;

The anode of the diode is connected to the drain of the field effect transistor, the cathode of the diode is connected to the anode of the electrolytic capacitor and the input end of the voltage stabilizing circuit, and the output end of the voltage stabilizing circuit is connected to the power input end of the control unit. The source of the FET, the cathode of the electrolytic capacitor, the ground of the voltage stabilizing circuit, and the ground of the control unit are connected to the common ground.

3. The LED lighting drive control circuit of claim 2, wherein:

The drain of the FET is connected as one end of the switch power take-off unit to the negative pole of the LED load, and the source of the FET is connected as the other end of the switch power take-off unit to the negative pole of the DC power source, by the FET One end of the drain as the power take-off unit is connected to the anode of the DC power source, and the source of the FET is used as the anode of the switch power take-off unit instead of the anode of the LED load.

4. The LED lighting drive control circuit of claim 1 wherein:

The switch power take-off unit includes at least one field effect transistor, a first resistor, a second resistor, a third resistor, a triode, and a diode, an electrolytic capacitor, and a voltage stabilizing circuit;

The drain of the FET is connected to the anode of the LED load as one end of the switch power take-off unit, and the source of the FET is connected to the anode of the DC power source as the other end of the switch power take-off unit, and the negative pole of the LED load a cathode of the DC power source is connected, a gate of the FET is connected to one end of the first resistor, and the other end of the first resistor is connected to a source of the FET, and one end of the second resistor is connected to the gate of the FET a pole connection, the other end of the second resistor is connected to the collector of the transistor, the base of the transistor is connected to one end of the third resistor, and the other end of the third resistor is connected to the signal output end of the control unit, the diode a cathode of the tube is connected to a drain of the field effect transistor, a cathode of the electrolytic capacitor is connected to a source of the field effect transistor and an input end of the voltage stabilizing circuit, and an output end of the voltage stabilizing circuit is connected to a power input end of the control unit The emitter of the triode, the anode of the diode, the cathode of the electrolytic capacitor, the ground of the voltage stabilizing circuit, and the ground of the control unit are connected to the common ground.

5. The LED lighting drive control circuit of claim 4, wherein:

The drain of the FET is connected to the anode of the LED load as one end of the switch power take-off unit, and the source of the FET is connected to the anode of the DC power source as the other end of the switch power take-off unit, and the negative pole of the LED load The negative pole connection of the DC power source is connected to the negative pole of the DC power source by the drain of the FET as the switch power take-off unit, and the source of the FET is connected to the cathode of the LED load as the other end of the switch power take-off unit. The positive pole of the LED load is replaced by the positive pole of the DC power supply.

6. An LED illumination drive control circuit according to any one of claims 1 to 5, characterized in that:

A resistor is connected in parallel across the LED load.

7. The LED lighting drive control circuit of claim 6 wherein:

The resistance of the resistor is calculated by R (U-Vc-Vd) /Is, U is the input voltage of the DC power supply, Vc is the lowest voltage at the input of the voltage regulator circuit to ensure normal operation, and Vd is the tube of the diode. Voltage drop, Is is the sum of the maximum current consumed by the control unit and the regulator circuit and the current lost during operation.

The LED illumination drive control circuit according to any one of claims 1 to 5, characterized in that:

The control unit includes a microcontroller or an integrated circuit;

The utility model further comprises an information input module, wherein the input mode is a key input mode or a touch input mode or an inductive input mode, and the signal output end of the information input module is connected to the signal input end of the microcontroller or the integrated circuit.

9. The LED lighting drive control circuit of claim 8 wherein:

The sensing input mode of the information input module is an infrared sensing mode or a human body pyroelectric induction mode.

The LED lighting drive control circuit according to any one of claims 1 to 5, characterized in that:

The control unit includes a microcontroller or an integrated circuit;

The method further includes a wireless transceiver circuit or an infrared remote control receiving circuit, wherein the signal output end is connected to the signal input end of the micro controller or the integrated circuit, and the power end end is connected to the power output end of the voltage stabilizing circuit.