CN209914115U - LED circuit - Google Patents

LED circuit Download PDF

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Publication number
CN209914115U
CN209914115U CN201920204782.9U CN201920204782U CN209914115U CN 209914115 U CN209914115 U CN 209914115U CN 201920204782 U CN201920204782 U CN 201920204782U CN 209914115 U CN209914115 U CN 209914115U
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resistor
capacitor
module
led
circuit
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吴永芳
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Guangzhou Shiyuan Electronics Thecnology Co Ltd
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Guangzhou Shiyuan Electronics Thecnology Co Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

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Abstract

The utility model relates to a LED circuit, include: the LED driving circuit comprises a driving control module, a driving module, an LED load module and a short-circuit protection module; the driving control module comprises a control signal output end and a short-circuit protection control end, and the driving module comprises an output end and a control signal input end; the control signal input end of the driving module is connected with the control signal output end of the driving control module, and the output end of the driving module is connected with the input end of the LED load module; the output end of the LED load module is connected with the short-circuit protection module; and the short-circuit protection module is used for sending a protection signal to the short-circuit protection control end of the drive control module when the LED load module is in short circuit so as to enable the control signal output end of the drive control module to stop outputting. The utility model discloses can avoid because LED load module short circuit damages drive control module, need not to set up protection IC specially to drive control module inside, with low costs and can effectively promote the circuit reliability.

Description

LED circuit
Technical Field
The utility model relates to a circuit protection field especially relates to a LED circuit.
Background
The LED liquid crystal television is the most common type on the market at present, and the constant current driving chip is a core element in a power supply of the LED liquid crystal television, and once the constant current driving chip is damaged, the normal operation of the LED liquid crystal television can be influenced.
In the backlight constant current power supply circuit of the television, the output end of the LED load module needs to be connected with the constant current driving chip, but once a light emitting diode in the LED load is short-circuited, the voltage of the input end of the LED load is higher than the voltage which can be borne by the constant current driving chip, the constant current driving chip is damaged, and other elements can be damaged seriously.
SUMMERY OF THE UTILITY MODEL
Therefore, there is a need for an LED circuit, which can stop the operation of the control circuit when the LED load is short-circuited, so as to avoid damage to the constant current driving chip and improve the safety of the circuit system.
An LED circuit, comprising: the LED driving circuit comprises a driving control module, a driving module, an LED load module and a short-circuit protection module; the driving control module comprises a control signal output end and a short-circuit protection control end, and the driving module comprises an output end and a control signal input end; the control signal input end of the driving module is connected with the control signal output end of the driving control module, the output end of the driving module is connected with the input end of the LED load module, and the driving module supplies energy through an external power supply; the output end of the LED load module is connected with the short-circuit protection module; and the short-circuit protection module is used for sending a protection signal to the short-circuit protection control end of the drive control module when the LED load module is in short circuit so as to enable the control signal output end of the drive control module to stop outputting.
In one embodiment, the short-circuit protection module comprises a detection unit and a control unit; the detection unit is used for sending a short-circuit signal to the control unit when detecting that the LED load is short-circuited; and the control unit is used for sending a protection signal to the drive control module when receiving the short-circuit signal.
In one embodiment, the driving control module comprises an LED constant current driving chip, and the LED constant current driving chip comprises a GATE pin and a COMP pin; the GATE pin is a control signal output end of the drive control module; and the COMP pin is a short-circuit protection control end of the drive control module.
In one embodiment, the control unit comprises a PNP triode, and the detection unit comprises an NPN triode and a first diode; the emitting electrode of the PNP triode is connected with the GATE pin of the LED constant current driving chip, the base electrode of the PNP triode is connected with the collecting electrode of the NPN triode, and the collecting electrode of the PNP triode is grounded; the collector of the NPN triode is connected with the power output end VCC of the LED constant current driving chip, the base of the NPN triode is connected with the cathode of the first diode, and the emitter of the NPN triode is grounded; the anode of the first diode is connected with the output end of the LED load module.
In one embodiment, the detection unit further comprises a first resistor, a second resistor, a third resistor and a first capacitor; the first end of the first resistor is connected with a power supply output end VCC of the LED constant current driving chip, and the second end of the first resistor is connected with a collector electrode of the NPN triode; the first end of the second resistor is connected with the base electrode of the NPN triode, and the second end of the second resistor is connected with the cathode of the first diode; the first end of the third resistor is connected with the base electrode of the NPN triode, and the second end of the third resistor is grounded; the first end of the first capacitor is connected with the base electrode of the NPN triode, and the second end of the first capacitor is grounded.
In one embodiment, the driving control module further includes a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a second capacitor, a third capacitor, a fourth capacitor, and a fifth capacitor; the LED constant current driving chip also comprises a brightness control signal end and a pulse width modulation end; the first end of the fourth resistor is connected with a power supply output end VCC of the LED constant current driving chip, and the second end of the fourth resistor is connected with a brightness control signal end; the first end of the fifth resistor is connected with the pulse width modulation end, and the second end of the fifth resistor is connected with the first end of the sixth resistor; the second end of the sixth resistor is connected with the second end of the fourth resistor; the first end of the seventh resistor is connected with the first end of the second capacitor, and the second end of the seventh resistor is used for receiving a brightness control signal; the second end of the second capacitor is connected with the first end of the third capacitor, and the second end of the third capacitor is connected with the brightness control signal end; the first end of the fourth capacitor is connected with a COMP pin of the LED constant current driving chip, and the second end of the fourth capacitor is connected with the first end of the eighth resistor; the second end of the eighth resistor is grounded; the first end of the fifth capacitor is connected with the COMP pin, and the second end of the fifth capacitor is grounded.
In one embodiment, the driving control module further includes a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a sixth capacitor, a seventh capacitor, and an eighth capacitor; the constant current driving chip also comprises an enabling end, a crystal oscillator end and an overvoltage protection end; the first end of the ninth resistor is connected with the crystal oscillator end, and the second end of the ninth resistor is grounded; the first end of the tenth resistor is used for current sampling, the second end of the tenth resistor is connected with the first end of the sixth capacitor, and the second end of the sixth capacitor is grounded; the first end of the eleventh resistor is used for receiving a starting signal, and the second end of the eleventh resistor is connected with the enabling end; the first end of the twelfth resistor is connected with the enabling end, and the second end of the twelfth resistor is grounded; the first end of the seventh capacitor is connected with the enabling end, and the second end of the seventh capacitor is grounded; the first end of the eighth capacitor is connected with the overvoltage protection end, and the second end of the eighth capacitor is grounded; and the thirteenth resistor is connected in parallel with two ends of the eighth capacitor.
In one embodiment, the driving module comprises a MOS transistor, an inductor, a fourteenth resistor, and a second diode; the grid electrode of the MOS tube is connected with a GATE pin of the LED constant current driving chip, the drain electrode of the MOS tube is connected with the first end of the inductor, the source electrode of the MOS tube is connected with the first end of the fourteenth resistor, and the second end of the fourteenth resistor is grounded; the first end of the inductor is connected with the anode of the second diode, and the second end of the inductor is used for connecting an input voltage end; and the cathode of the second diode is connected with the input end of the LED load module.
In one embodiment, the driving module further includes a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a ninth capacitor, and a third diode; the first end of the fifteenth resistor is connected with the GATE pin, the second end of the fifteenth resistor is connected with the cathode of the third diode, and the anode of the third diode is connected with the grid electrode of the MOS tube; the first end of the sixteenth resistor is connected with the grid electrode of the MOS tube, and the second end of the sixteenth resistor is connected with the source electrode of the MOS tube; the first end of the seventeenth resistor is connected with the GATE pin, and the second end of the seventeenth resistor is connected with the grid electrode of the MOS tube; a first end of the eighteenth resistor is connected with the cathode of the second diode, and a second end of the eighteenth resistor is connected with a first end of the nineteenth resistor; the second end of the nineteenth resistor is connected with the overvoltage protection end; and the first end of the ninth capacitor is connected with the cathode of the second diode, and the second end of the ninth capacitor is grounded.
In one embodiment, the LED load module comprises more than one LED series units, and the LED series units are mutually connected in parallel; each light emitting diode series unit comprises more than one light emitting diode.
The LED circuit comprises a short-circuit protection module, a driving module, a short-circuit protection module, a high-level input module, a high-level output module, a short-circuit protection module, a driving control module and a control module, wherein the short-circuit protection module is arranged in the circuit and connected with the output end of the LED load module, when the LED load module is in short circuit, the LED load module is equivalent to a wire, the short-circuit protection module is communicated with the output end of the driving module, the voltage input into the short-circuit protection module is higher than the voltage of the LED load module during normal working at the moment, which is equivalent to the input of the high level, the short-circuit protection module is communicated at the moment, a protection signal is sent to the short-circuit protection control end of the driving control module, the driving control module stops outputting the control signal output end after receiving the protection signal, thereby realizing.
Drawings
FIG. 1 is a schematic diagram of an embodiment of an LED circuit;
FIG. 2 is a schematic diagram of a circuit configuration of an LED circuit according to an embodiment;
fig. 3 is a schematic circuit diagram of an LED circuit according to another embodiment.
Detailed Description
In order to facilitate understanding of the present invention, the present invention will be described more fully below. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
In a specific embodiment, an LED circuit, shown in conjunction with fig. 1, comprises: a driving control module 110, a driving module 120, an LED load module 130 and a short-circuit protection module 140; the driving control module 110 includes a control signal output terminal and a short-circuit protection control terminal, and the driving module 120 includes an output terminal and a control signal input terminal; the control signal input end of the driving module 120 is connected with the control signal output end of the driving control module 110, the output end of the driving module 120 is connected with the input end of the LED load module 130, and the driving module supplies energy through an external power supply; the output end of the LED load module 130 is connected to the short-circuit protection module 140; the short-circuit protection module 140 is configured to send a protection signal to the short-circuit protection control end of the driving control module 110 when the LED load module 130 is in a short circuit, so that the control signal output end of the driving control module 110 stops outputting. The short-circuit protection module is arranged in the circuit and is connected with the output end of the LED load module, when the LED load module is in short circuit, the LED load module is equivalent to a wire, the short-circuit protection module is communicated with the output end of the driving module, the voltage input into the short-circuit protection module is higher than the voltage of the LED load module during normal work at the moment, and is equivalent to input of a high level, because the high level of the short-circuit protection module is conducted, the short-circuit protection module is conducted at the moment, a protection signal is sent to the short-circuit protection control end of the driving control module, after the driving control module receives the protection signal, the output of the control signal output end is stopped to continue outputting, the protection of the circuit is realized, the driving control module is prevented from being damaged due to the short circuit of the LED load module, a protection.
In one embodiment, the short-circuit protection module 140 includes a detection unit and a control unit; the detection unit is used for sending a short-circuit signal to the control unit when detecting that the LED load 130 is short-circuited; and a control unit, configured to send a protection signal to the driving control module 110 when receiving the short-circuit signal.
In one embodiment, as shown in fig. 2, the driving control module 110 includes an LED constant current driving chip U1, and the LED constant current driving chip U1 includes a GATE pin and a COMP pin; the GATE pin is a control signal output terminal of the driving control module 110; the COMP pin is a short-circuit protection control terminal of the driving control module 110.
The GATE pin is used for connecting a control signal input end of the driving module 120, and when the driving control module 110 inputs a working signal to the control signal input end of the driving module 120 through the GATE pin, the driving module 120 enters a working state to provide a working voltage for the LED load module 130; the COMP pin is used for receiving a protection signal sent by the short-circuit protection module 140, when the LED load module 130 is short-circuited, the working voltage output by the driving module 120 is directly input to the short-circuit protection module 140, at this time, the short-circuit protection module 140 is turned on at a high level to work, a protection signal is sent to the COMP pin, and the LED constant current driving chip U1 controls the GATE pin to stop outputting a signal.
In one embodiment, referring to fig. 2, the control unit includes a PNPPNP transistor Q1, the detection unit includes an NPN transistor Q2, and a first diode D1; an emitting electrode of the PNP triode Q1 is connected with a GATE pin of the LED constant current driving chip, a base electrode of the PNP triode Q1 is connected with a collector electrode of the NPN triode Q2, and the collector electrode of the PNP triode Q1 is grounded; a collector of the NPN triode Q2 is connected with a power output end VCC of the LED constant current driving chip, a base of the NPN triode Q2 is connected with a cathode of the first diode D1, and an emitter of the NPN triode Q2 is grounded; the anode of the first diode D1 is connected to the output of the LED load module 130.
The PNP transistor Q1 is a PNP transistor and is turned on at a low level, and the NPN transistor Q2 is an NP transistor and is turned on at a high level. When the LED load module 130 is short-circuited, the voltage output by the driving module 120 is equivalent to be directly input to the base of the NPN triode Q2 through the first diode D1, the NPN triode Q2 is turned on, because the base of the PNP triode Q1 is connected to the collector of the NPN triode Q2, when the NPN triode Q2 is turned on, the base of the PNP triode Q1 is equivalent to be grounded, at this time, the low level of the PNP triode Q1 is turned on, and the voltage of the COMP pin is pulled down, so that the constant current driving chip U1 controls the GATE pin stop signal to be output, thereby protecting the power circuit. The first diode D1 is provided to prevent the NPN transistor Q2 from generating a reverse voltage to damage the LED load module 130 during state switching.
In one embodiment, referring to fig. 2, the detecting unit further includes a first resistor R1, a second resistor R2, a third resistor R3, and a first capacitor C1; the first end of the first resistor R1 is connected with a power output end VCC of the LED constant current driving chip, and the second end is connected with a collector of an NPN triode Q2; a first end of the second resistor R2 is connected with the base of the NPN triode Q2, and a second end is connected with the cathode of the first diode D1; the first end of the third resistor R3 is connected with the base of the NPN triode Q2, and the second end is grounded; the first end of the first capacitor C1 is connected to the base of the NPN transistor Q2, and the second end is grounded.
The first resistor R1 is a load resistor, so that the voltage of the collector of the NPN triode Q2 changes along with the change of the base current, and the current amplification effect is achieved; the second resistor R2 is used for providing base bias voltage for the NPN triode Q2; the third resistor R3 is used for grounding the base of the NPN triode Q2 through the third resistor R3 when the LED load module 130 is working normally, so as to ensure that the NPN triode Q2 is in a cut-off state; the first capacitor C1 is a filter capacitor.
In one embodiment, as shown in fig. 3, the driving control module 110 further includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, and a fifth capacitor C5; the LED constant current driving chip U1 further comprises a brightness control signal end and a pulse width modulation end; a first end of the fourth resistor R4 is connected with a power output end VCC of the LED constant current driving chip U1, and a second end is connected with a brightness control signal end; the first end of the fifth resistor R5 is connected with the pulse width modulation end, and the second end is connected with the first end of the sixth resistor R6; a second end of the sixth resistor R6 is connected with a second end of the fourth resistor R4; a first end of the seventh resistor R7 is connected to a first end of the second capacitor C2, and a second end is used for receiving the brightness control signal; a second end of the second capacitor C2 is connected to a first end of the third capacitor C3, and a second end of the third capacitor C3 is connected to the luminance control signal end; a first end of the fourth capacitor C4 is connected with a COMP pin of the LED constant current driving chip, and a second end of the fourth capacitor C4 is connected with a first end of the eighth resistor R8; a second end of the eighth resistor R8 is grounded; the first end of the fifth capacitor C5 is connected to the COMP pin, and the second end is grounded.
A COMP pin is a compensation end of a constant current driving chip U1, and an eighth resistor R8, a fourth capacitor C4 and a fifth capacitor C5 are used for loop compensation, so that the stability of the circuit is improved; the pulse width modulation end, the brightness control signal end, the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, the second capacitor C2 and the third capacitor C3 are used for realizing LED brightness control, and the brightness of the LED can be controlled by modulating the pulse width.
In one embodiment, as shown in fig. 3, the driving control module 110 further includes a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a sixth capacitor C6, a seventh capacitor C7, and an eighth capacitor C8; the LED constant current driving chip U1 further comprises an enabling end, a crystal oscillator end and an overvoltage protection end; a first end of the ninth resistor R9 is connected with the crystal oscillator end, and a second end is grounded; a first end of the tenth resistor R10 is used for current sampling, a second end of the tenth resistor R10 is connected to a first end of the sixth capacitor C6, and a second end of the sixth capacitor C6 is grounded; the first end of the eleventh resistor R11 is used for receiving a turn-on signal, and the second end is connected with the enable end; a first end of the twelfth resistor R12 is connected with the enabling end, and a second end is grounded; a first end of the seventh capacitor C7 is connected with the enabling end, and a second end is grounded; the first end of the eighth capacitor C8 is connected with the overvoltage protection end, and the second end is grounded; the thirteenth resistor R13 is connected in parallel across the eighth capacitor.
The enable terminal, the crystal oscillator terminal, the eleventh resistor R11, the twelfth resistor R12, the seventh capacitor C7 and the ninth resistor R9 jointly play a role in enabling control and crystal oscillation; the tenth resistor R10, the sixth capacitor C6, the eighth capacitor C8, the thirteenth resistor R13 and the overvoltage protection end are overvoltage protection circuits, and input working voltage of the LED load module is sampled and detected through the tenth resistor.
In one embodiment, referring to fig. 3, the driving module 120 includes a MOS transistor Q3, an inductor L, a fourteenth resistor R14, and a second diode D2; the GATE of the MOS transistor Q3 is connected to the GATE pin of the LED constant current driving chip U1, the drain is connected to the first end of the inductor L, the source is connected to the first end of the fourteenth resistor R14, and the second end of the fourteenth resistor R14 is grounded; a first end of the inductor L is connected to an anode of the second diode D2, and a second end of the inductor L is used for connecting the input voltage terminal VBL; the cathode of the second diode D2 is connected to the input of the LED load module 130.
When the GATE pin of the constant current driving chip U1 outputs a signal to the MOS transistor Q3 to control the conduction of the MOS transistor Q3, the inductor L is equivalent to ground to form a loop, at this time, the input voltage VBL charges the inductor L, after the charging of the inductor L is completed, the GATE pin controls the MOS transistor to be turned off, the inductor L starts to discharge, the input voltage VBL is boosted, and the working voltage LED + is output to the LED load module 130, and the second diode D2 is used for preventing the reverse voltage from damaging the circuit. The fourteenth resistor R14 is used for current sampling, and the first end of the tenth resistor is connected with the first end of the fourteenth resistor R14 for sampling and monitoring the loop current.
In some embodiments, the MOS transistor Q3 may be an N-type MOS transistor, and those skilled in the art may also change the MOS transistor to a P-type MOS transistor according to actual needs.
In one embodiment, as shown in fig. 3, the driving module 120 further includes a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a ninth capacitor C9, and a third diode D3; a first end of the fifteenth resistor R15 is connected to the GATE pin, a second end is connected to the cathode of the third diode D3, and the anode of the third diode D3 is connected to the GATE of the MOS transistor Q3; a first end of the sixteenth resistor R16 is connected to the gate of the MOS transistor Q3, and a second end is connected to the source of the MOS transistor Q3; a first end of the seventeenth resistor R17 is connected to the GATE pin, a second end of the seventeenth resistor R17 is connected to the GATE of the MOS transistor Q3, a first end of the eighteenth resistor R18 is connected to the cathode of the second diode D2, and a second end of the seventeenth resistor R19 is connected to the first end of the nineteenth resistor R19; a second end of the nineteenth resistor R19 is connected with an overvoltage protection end; the ninth capacitor C9 has a first terminal connected to the cathode of the second diode D2 and a second terminal connected to ground.
The seventeenth resistor R17 is used for limiting current and preventing the MOS transistor Q3 from being broken down; the fifteenth resistor R15 and the third diode D3 can slow down the conduction speed of the MOS transistor Q3 and prevent over-driving; the sixteenth resistor R16 can protect the gate and source.
The eighteenth resistor R18 and the nineteenth resistor R19 are connected in series and then connected to the overvoltage protection terminal of the constant current driving chip U1, and are used for detecting the working voltage input to the LED load module 130, thereby playing a role of overvoltage protection; the ninth capacitor C9 is a filter capacitor, and the second diode D2 can prevent the ninth capacitor C9 from discharging to generate a reverse voltage to damage the input voltage source.
In one embodiment, as shown in fig. 3, the LED load module 130 includes more than one LED series units, and the LED series units are connected in parallel; each light emitting diode series unit comprises more than one light emitting diode.
The LED load module 130 includes LED series units, each LED series unit is composed of one or more LEDs connected in series, the specific number can be selected according to actual needs, the number of the LED series units can also be selected according to actual needs, and can be one or multiple, when the number of the LED series units is two or more, the LED series units are connected in parallel.
In order to adapt the number of the led series units, the short-circuit protection module 140 should also add the same number of diodes, and the cathode is connected to the second resistor R2, and the anode is connected to the led series units to prevent the reverse current from damaging the leds.
In some embodiments, the LED constant current driving chip U1 may be OB2532, OB3350, OB3363, etc., and those skilled in the art may select other models according to specific situations.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims (10)

1. An LED circuit, comprising: the LED driving circuit comprises a driving control module, a driving module, an LED load module and a short-circuit protection module;
the driving control module comprises a control signal output end and a short-circuit protection control end, and the driving module comprises an output end and a control signal input end;
the control signal input end of the driving module is connected with the control signal output end of the driving control module, the output end of the driving module is connected with the input end of the LED load module, and the driving module supplies energy through an external power supply;
the output end of the LED load module is connected with the short-circuit protection module;
and the short-circuit protection module is used for sending a protection signal to the short-circuit protection control end of the drive control module when the LED load module is in short circuit so as to enable the control signal output end of the drive control module to stop outputting.
2. The LED circuit of claim 1, wherein the short-circuit protection module comprises a detection unit and a control unit;
the detection unit is used for sending a short-circuit signal to the control unit when the LED load is detected to be short-circuited;
and the control unit is used for sending a protection signal to the drive control module when receiving the short-circuit signal.
3. The LED circuit of claim 2, wherein the driving control module comprises an LED constant current driving chip, the LED constant current driving chip comprises a GATE pin and a COMP pin,
the GATE pin is a control signal output end of the drive control module;
and the COMP pin is a short-circuit protection control end of the drive control module.
4. The LED circuit of claim 3, wherein the control unit comprises a PNP transistor,
the detection unit comprises an NPN triode and a first diode;
the emitting electrode of the PNP triode is connected with the GATE pin of the LED constant current driving chip, the base electrode of the PNP triode is connected with the collecting electrode of the NPN triode, and the collecting electrode of the PNP triode is grounded;
the collector of the NPN triode is connected with the power output end VCC of the LED constant current driving chip, the base of the NPN triode is connected with the cathode of the first diode, and the emitter of the NPN triode is grounded;
and the anode of the first diode is connected with the output end of the LED load module.
5. The LED circuit of claim 4, wherein the detection unit further comprises a first resistor, a second resistor, a third resistor, and a first capacitor;
the first end of the first resistor is connected with a power supply output end VCC of the LED constant current driving chip, and the second end of the first resistor is connected with a collector electrode of the NPN triode;
the first end of the second resistor is connected with the base electrode of the NPN triode, and the second end of the second resistor is connected with the cathode of the first diode;
the first end of the third resistor is connected with the base electrode of the NPN triode, and the second end of the third resistor is grounded;
the first end of the first capacitor is connected with the base electrode of the NPN triode, and the second end of the first capacitor is grounded.
6. The LED circuit of claim 3, wherein the driving control module further comprises a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a second capacitor, a third capacitor, a fourth capacitor, and a fifth capacitor;
the LED constant current driving chip also comprises a brightness control signal end and a pulse width modulation end;
the first end of the fourth resistor is connected with a power supply output end VCC of the LED constant current driving chip, and the second end of the fourth resistor is connected with the brightness control signal end;
the first end of the fifth resistor is connected with the pulse width modulation end, and the second end of the fifth resistor is connected with the first end of the sixth resistor;
the second end of the sixth resistor is connected with the second end of the fourth resistor;
the first end of the seventh resistor is connected with the first end of the second capacitor, and the second end of the seventh resistor is used for receiving a brightness control signal;
the second end of the second capacitor is connected with the first end of the third capacitor, and the second end of the third capacitor is connected with the brightness control signal end;
the first end of the fourth capacitor is connected with a COMP pin of the LED constant current driving chip, and the second end of the fourth capacitor is connected with the first end of the eighth resistor;
a second end of the eighth resistor is grounded;
and the first end of the fifth capacitor is connected with the COMP pin, and the second end of the fifth capacitor is grounded.
7. The LED circuit of claim 3, wherein the driving control module further comprises a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a sixth capacitor, a seventh capacitor, and an eighth capacitor;
the constant current driving chip also comprises an enabling end, a crystal oscillator end and an overvoltage protection end;
the first end of the ninth resistor is connected with the crystal oscillator end, and the second end of the ninth resistor is grounded;
a first end of the tenth resistor is used for current sampling, a second end of the tenth resistor is connected with a first end of the sixth capacitor, and a second end of the sixth capacitor is grounded;
the first end of the eleventh resistor is used for receiving a starting signal, and the second end of the eleventh resistor is connected with the enabling end;
the first end of the twelfth resistor is connected with the enabling end, and the second end of the twelfth resistor is grounded;
the first end of the seventh capacitor is connected with the enabling end, and the second end of the seventh capacitor is grounded;
the first end of the eighth capacitor is connected with the overvoltage protection end, and the second end of the eighth capacitor is grounded;
the thirteenth resistor is connected in parallel to two ends of the eighth capacitor.
8. The LED circuit of claim 7, wherein the driving module comprises a MOS transistor, an inductor, a fourteenth resistor and a second diode;
the grid electrode of the MOS tube is connected with a GATE pin of the LED constant current driving chip, the drain electrode of the MOS tube is connected with the first end of the inductor, the source electrode of the MOS tube is connected with the first end of the fourteenth resistor, and the second end of the fourteenth resistor is grounded;
the first end of the inductor is connected with the anode of the second diode, and the second end of the inductor is used for being connected with an input voltage end;
and the cathode of the second diode is connected with the input end of the LED load module.
9. The LED circuit of claim 8, wherein the driving module further comprises a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a ninth capacitor, and a third diode;
a first end of the fifteenth resistor is connected with the GATE pin, a second end of the fifteenth resistor is connected with a cathode of the third diode, and an anode of the third diode is connected with a GATE of the MOS transistor;
the first end of the sixteenth resistor is connected with the grid electrode of the MOS tube, and the second end of the sixteenth resistor is connected with the source electrode of the MOS tube;
the first end of the seventeenth resistor is connected with the GATE pin, and the second end of the seventeenth resistor is connected with the grid electrode of the MOS tube;
a first end of the eighteenth resistor is connected with the cathode of the second diode, and a second end of the eighteenth resistor is connected with a first end of the nineteenth resistor;
the second end of the nineteenth resistor is connected with the overvoltage protection end;
and the first end of the ninth capacitor is connected with the cathode of the second diode, and the second end of the ninth capacitor is grounded.
10. The LED circuit of claim 8, wherein the LED load module comprises more than one LED series units, and the LED series units are connected in parallel with each other;
each light emitting diode series unit comprises more than one light emitting diode.
CN201920204782.9U 2019-02-18 2019-02-18 LED circuit Active CN209914115U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201920204782.9U CN209914115U (en) 2019-02-18 2019-02-18 LED circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201920204782.9U CN209914115U (en) 2019-02-18 2019-02-18 LED circuit

Publications (1)

Publication Number Publication Date
CN209914115U true CN209914115U (en) 2020-01-07

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Family Applications (1)

Application Number Title Priority Date Filing Date
CN201920204782.9U Active CN209914115U (en) 2019-02-18 2019-02-18 LED circuit

Country Status (1)

Country Link
CN (1) CN209914115U (en)

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