CN109587890B - Driver circuit of LED lamp - Google Patents
Driver circuit of LED lamp Download PDFInfo
- Publication number
- CN109587890B CN109587890B CN201811633015.6A CN201811633015A CN109587890B CN 109587890 B CN109587890 B CN 109587890B CN 201811633015 A CN201811633015 A CN 201811633015A CN 109587890 B CN109587890 B CN 109587890B
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- led
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- 230000000087 stabilizing effect Effects 0.000 claims abstract description 46
- 238000001514 detection method Methods 0.000 claims abstract description 29
- 238000001914 filtration Methods 0.000 claims abstract description 10
- 239000003990 capacitor Substances 0.000 claims description 26
- 238000004804 winding Methods 0.000 claims description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000005286 illumination Methods 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/50—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
Abstract
The invention discloses a driver circuit of an LED lamp, which is characterized by comprising an overcurrent protection unit, a rectifying and filtering unit, a +5V voltage stabilizing unit, a reference voltage unit, an LED driver constant current unit, a fault detection unit, a display module driving unit and a display module unit. The LED lamp driver circuit has the advantages that the LED lamp driver circuit consists of an overcurrent protection unit, a rectifying and filtering unit, a +5V voltage stabilizing unit, a reference voltage unit, an LED driver constant current unit, a fault detection unit, a display module driving unit and a display module unit, the fault detection unit is used for detecting the voltage change of the signal output end of the LED+/LED of the LED driving constant current unit in real time, and outputting corresponding high-low level voltage to the display module driving unit, and the display module driving unit is used for driving the display module unit to send out corresponding alarm prompts, so that the LED lamp has fault detection and alarm functions.
Description
Technical Field
The invention relates to the field of illumination, in particular to a driver circuit of an LED lamp.
Background
The LED lamp has the characteristics of energy conservation, environmental protection, high efficiency, low carbon and the like, and is gradually applied to the field of illumination instead of the traditional illumination lamp. The safe reliability of the LED lamp is a problem which is generally focused at present, if faults such as internal short circuit and open circuit of the LED lamp are not found in time, the failed LED lamp can cause phenomena such as heavy current and serious heat in the LED lamp under the condition of electrifying, and then the electronic components in the LED lamp are burnt out, even the whole LED lamp is burnt out under the serious condition, fire disaster occurs, and great potential safety hazard exists. At present, the conventional driver circuit of the LED lamp is generally used for driving the LED lamp to emit light, and does not have fault monitoring and alarming functions.
Disclosure of Invention
The invention aims to solve the technical problem of providing a driver circuit of an LED lamp with simple structure and fault detection and alarm functions.
The technical scheme adopted for solving the technical problems is as follows:
a driver circuit of an LED lamp comprises an overcurrent protection unit, a rectifying and filtering unit, a +5V voltage stabilizing unit, a reference voltage unit, an LED driver constant current unit, a fault detection unit, a display module driving unit and a display module unit;
the input end of the overcurrent protection unit is connected with the alternating current of the mains supply, the AC signal output end of the overcurrent protection unit is connected with the AC signal input end of the rectification filter unit, the V+ signal output end of the rectification filter unit is respectively connected with the V+ signal input end of the +5V voltage stabilizing unit and the V+ signal input end of the LED driver constant current unit, the V-signal output end of the rectification filter unit is respectively connected with the V-signal input end of the +5V voltage stabilizing unit and the V-signal input end of the LED driver constant current unit, the +5V signal output end and the GND end of the +5V voltage stabilizing unit are respectively connected with the +5V voltage stabilizing signal input end of the reference voltage unit, the LED+ signal output end and the LED-signal output end of the LED driver constant current unit are respectively connected with the LED+ detection signal input end and the LED-detection signal input end of the fault detection unit, the driving control signal output end of the fault detection unit is respectively connected with the display module, and the driving module of the driving module is connected with the three-way signal input end of the display module, and the driving module is connected with the output end of the display module.
The reference voltage unit comprises a voltage stabilizing chip, a first resistor, a second resistor, a third resistor and a first capacitor, wherein a common end formed by connecting an A pin of the voltage stabilizing chip with a first pin of the third resistor forms a third pin of the reference voltage unit, a second pin of the third resistor forms a first pin of the reference voltage unit, a common end formed by connecting a B pin of the voltage stabilizing chip with the first pin of the first resistor is connected with the first pin of the first capacitor, a common end formed by connecting a second pin of the first resistor with the first pin of the second resistor forms a fourth pin of the reference voltage unit, and a common end formed by connecting a second pin of the second resistor with a second pin of the first capacitor is connected with a GND pin of the voltage stabilizing chip to form a second pin of the reference voltage unit.
The fault detection unit comprises a voltage comparison chip, a first diode, a fourth resistor, a fifth resistor and a second capacitor, wherein the positive electrode of the first diode is connected with the LED+ signal output end of the LED driving constant current unit, the negative electrode of the first diode is connected with the first pin of the fifth resistor, the second pin of the fifth resistor is connected with the fifth pin of the voltage comparison chip, the first pin of the fourth resistor is connected with the LED-signal output end of the LED driving constant current unit, the common end formed by the second pin of the fourth resistor and the first pin of the second capacitor is connected with the third pin of the voltage comparison chip, the second pin of the second capacitor, the fourth pin of the voltage comparison chip, the second pin of the reference voltage unit and the GND end of the +5V voltage unit are connected and grounded, the second pin of the voltage comparison chip is connected with the fourth pin of the reference voltage unit, the common end of the voltage comparison chip is connected with the voltage of the eighth pin of the voltage comparison chip, and the voltage of the eighth pin of the voltage comparison unit is connected with the voltage comparison unit forms the +5V.
The display module unit comprises a buzzer, a red indicator lamp, a yellow indicator lamp and a sixth resistor, wherein the anodes of the buzzer, the red indicator lamp and the yellow indicator lamp are connected to form a common end to be connected with the +5V output end of the +5V voltage stabilizing unit, the cathode of the red indicator lamp is connected with the first pin of the sixth resistor, and the second pin of the sixth resistor is grounded.
The display module driving unit comprises a first triode, a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor, wherein the base electrode of the first triode is connected with the first pin of the ninth resistor, the second pin of the ninth resistor is connected with the first pin of the tenth resistor, the second pin of the tenth resistor is connected with the negative electrode of the yellow indicator, the collector electrode of the first triode is connected with the first pin of the seventh resistor, the second pin of the seventh resistor is grounded, the common end formed by connecting the emitter electrode of the first triode with the negative electrode of the buzzer is connected with the first pin of the eighth resistor, the second pin of the eighth resistor is connected with the +5V output end of the +5V voltage stabilizing unit, and the common end formed by connecting the first pin of the voltage comparison chip with the seventh pin is connected with the common end formed by connecting the ninth resistor with the tenth resistor.
The overcurrent protection unit comprises a wire winding fuse resistor, the rectifying and filtering unit comprises a rectifying bridge and a third capacitor, a first pin of the wire winding fuse resistor is connected with a commercial power alternating current end, a second pin of the wire winding fuse resistor is connected with the first pin of the rectifying bridge, the second pin of the rectifying bridge is connected with the commercial power alternating current end, a common end formed by connecting the third pin of the rectifying bridge with the first pin of the third capacitor is connected with a V+ signal input end of the +5V voltage stabilizing unit, and a common end formed by connecting the fourth pin of the rectifying bridge with the second pin of the third capacitor is connected with a V-signal input end of the +5V voltage stabilizing unit.
Compared with the prior art, the invention has the advantages that: the driver circuit of the LED lamp consists of an overcurrent protection unit, a rectifying and filtering unit, a +5V voltage stabilizing unit, a reference voltage unit, an LED driver constant current unit, a fault detection unit, a display module driving unit and a display module unit, wherein the fault detection unit is used for detecting the voltage change of the signal output end of the LED+/LED of the LED driving constant current unit in real time and outputting corresponding high-low level voltage to the display module driving unit, and the display module driving unit is used for driving the display module unit to send out corresponding alarm prompt.
Drawings
FIG. 1 is a schematic block diagram of the present invention;
FIG. 2 is a general circuit schematic of the present invention;
FIG. 3 is a schematic diagram of a reference voltage unit according to the present invention;
FIG. 4 is a schematic circuit diagram of a display module unit according to the present invention;
FIG. 5 is a schematic circuit diagram showing the cooperative connection of an overcurrent protection unit, a rectifying and filtering unit, a +5V voltage stabilizing unit and an LED driver constant current unit;
fig. 6 is a schematic circuit diagram of the connection of the fault detection unit, the reference voltage unit and the display module driving unit in the present invention.
Description of the embodiments
The invention is described in further detail below with reference to the embodiments of the drawings.
As shown in fig. 1 to 6, a driver circuit of an LED lamp includes an overcurrent protection unit, a rectifying and filtering unit, +5v voltage stabilizing unit, a reference voltage unit, an LED driver constant current unit, a fault detection unit, a display module driving unit, and a display module unit;
the input end of the overcurrent protection unit is connected with mains alternating current, the AC signal output end of the overcurrent protection unit is connected with the AC signal input end of the rectification filter unit, the V+ signal output end of the rectification filter unit is respectively connected with the V+ signal input end of the +5V voltage stabilizing unit and the V+ signal input end of the LED driver constant current unit, the V-signal output end of the rectification filter unit is respectively connected with the V-signal input end of the +5V voltage stabilizing unit and the V-signal input end of the LED driver constant current unit, the +5V signal output end and the GND end of the +5V voltage stabilizing unit are respectively connected with the +5V voltage stabilizing signal input end of the reference voltage unit, the LED+ signal output end and the LED-signal output end of the LED driver constant current unit are respectively connected with the LED+ detection signal input end and the LED-detection signal input end of the fault detection unit, the driving control signal output end of the fault detection unit is connected with the driving control signal input end of the display module driving unit, the three paths of the output signal line of the reference voltage unit is connected with the three paths of the control signal line of the input end of the fault detection unit, and the display module driving unit is connected with the voltage signal output end of the display module driving unit.
In this specific embodiment, the LED driver constant current unit may employ a constant current switching chip of a conventional LED driver, such as BP3339, SY5830, and the like.
In this specific embodiment, the reference voltage unit includes a voltage stabilizing chip U1, a first resistor R1, a second resistor R2, a third resistor R3, and a first capacitor C1, where a common end formed by connecting an a pin of the voltage stabilizing chip U1 and a first pin of the third resistor R3 forms a third pin of the reference voltage unit, a second pin of the third resistor R3 forms a first pin of the reference voltage unit, a common end formed by connecting a B pin of the voltage stabilizing chip U1 and a first pin of the first resistor R1 is connected with a first pin of the first capacitor C1, a common end formed by connecting a second pin of the first resistor R1 and a first pin of the second resistor R2 forms a fourth pin of the reference voltage unit, and a common end formed by connecting a second pin of the second resistor R2 and a second pin of the first resistor R1 is connected with a GND pin of the voltage stabilizing chip U1.
In this embodiment, the voltage stabilizing chip U1 may be a constant voltage switching chip of a conventional LED driver, such as OB2500N, BP 2519.
In this embodiment, the fault detection unit includes a voltage comparison chip U2, a first diode D1, a fourth resistor R4, a fifth resistor R5, and a second capacitor C2, where an anode of the first diode D1 is connected to an led+ signal output terminal of the LED driving constant current unit, a cathode of the first diode D1 is connected to a first pin of the fifth resistor R5, a second pin of the fifth resistor R5 is connected to a fifth pin of the voltage comparison chip U2, a first pin of the fourth resistor R4 is connected to an LED driving constant current unit LED-signal output terminal, a common terminal formed by connecting the second pin of the fourth resistor R4 and the first pin of the second capacitor C2 is connected to a third pin of the voltage comparison chip U2, a second pin of the second capacitor C2, a fourth pin of the reference voltage unit, and a GND terminal of the +5v voltage stabilizing unit are connected to ground, a second pin of the voltage comparison chip U2 is connected to a fourth pin of the reference voltage unit, a sixth pin of the voltage comparison chip U2 is connected to a sixth pin of the reference voltage unit, and a common terminal of the eighth voltage unit is connected to a reference voltage unit V5.
In this embodiment, the voltage comparison chip may be an LM393 chip.
In this specific embodiment, the display module unit includes a buzzer B1, a red indicator LED1, a yellow indicator LED2, and a sixth resistor R6, where the anodes of the buzzer B1, the red indicator LED1, and the yellow indicator LED2 are connected to form a common terminal and connected to the +5v output terminal of the +5v voltage stabilizing unit, and the cathode of the red indicator LED1 is connected to the first pin of the sixth resistor R6, and the second pin of the sixth resistor R6 is grounded.
In this embodiment, the display module unit is mounted on the surface of the body of the LED lamp.
In this embodiment, the display module driving unit includes a first triode Q1, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, and a tenth resistor R10, where the base of the first triode Q1 is connected to the first pin of the ninth resistor R9, the second pin of the ninth resistor R9 is connected to the first pin of the tenth resistor R10, the second pin of the tenth resistor R10 is connected to the negative electrode of the yellow indicator, the collector of the first triode Q1 is connected to the first pin of the seventh resistor R7, the second pin of the seventh resistor R7 is grounded, the common end formed by connecting the emitter of the first triode Q1 and the negative electrode of the buzzer B1 is connected to the first pin of the eighth resistor R8, the second pin of the eighth resistor R8 is connected to the +5v output end of the +5v voltage stabilizing unit, and the common end formed by connecting the first pin of the voltage comparison chip U2 and the seventh pin is connected to the common end formed by connecting the ninth resistor R9 and the tenth resistor R10.
In this specific embodiment, the overcurrent protection unit includes a wire-wound fuse resistor R, the rectifying and filtering unit includes a rectifying bridge D2 and a third capacitor C3, a first pin of the wire-wound fuse resistor R is connected to the ac mains terminal, a second pin of the wire-wound fuse resistor R is connected to the first pin of the rectifying bridge D2, the second pin of the rectifying bridge D2 is connected to the ac mains terminal, a common end formed by connecting the third pin of the rectifying bridge D2 and the first pin of the third capacitor C3 is connected to the v+ signal input end of the +5v voltage stabilizing unit, and a common end formed by connecting the fourth pin of the rectifying bridge D2 and the second pin of the third capacitor C3 is connected to the V-signal input end of the +5v voltage stabilizing unit.
When faults such as short circuit and circuit break occur in the LED lamp, the voltage of the signal output end of the LED+/LED of the LED driving constant current unit changes to a certain extent, the fault detection unit monitors the voltage change of the LED+/LED in real time, when abnormal voltage change is detected, the output end of the fault detection unit outputs corresponding high-low level voltage to the display module driving unit through the control of the voltage comparison chip, the display module driving unit outputs voltage suitable for starting of a buzzer and an indicator lamp in the display module unit through the processing of the high-low level voltage, and therefore the indicator lamp is lightened, the buzzer alarms, and the fault alarm function is achieved.
Claims (1)
1. The driver circuit of the LED lamp is characterized by comprising an overcurrent protection unit, a rectifying and filtering unit, a +5V voltage stabilizing unit, a reference voltage unit, an LED driver constant current unit, a fault detection unit, a display module driving unit and a display module unit;
the input end of the overcurrent protection unit is connected with the alternating current of the mains supply, the AC signal output end of the overcurrent protection unit is connected with the AC signal input end of the rectification filter unit, the V+ signal output end of the rectification filter unit is respectively connected with the V+ signal input end of the +5V voltage stabilizing unit and the V+ signal input end of the LED driver constant current unit, the V-signal output end of the rectification filter unit is respectively connected with the V-signal input end of the +5V voltage stabilizing unit and the V-signal input end of the LED driver constant current unit, the +5V signal output end and the GND end of the +5V voltage stabilizing unit are respectively connected with the +5V voltage stabilizing signal input end of the reference voltage unit, the LED+ signal output end of the LED driver constant current unit and the LED-signal output end of the LED-constant current unit are respectively connected with the LED+ detection signal input end and the LED-detection signal input end of the fault detection unit, the driving control signal output end of the fault detection unit is respectively connected with the display module of the three-way signal driving unit, and the driving module of the display module is connected with the output voltage of the display module;
the reference voltage unit comprises a voltage stabilizing chip, a first resistor, a second resistor, a third resistor and a first capacitor, wherein a common end formed by connecting an A pin of the voltage stabilizing chip with a first pin of the third resistor forms a third pin of the reference voltage unit, a second pin of the third resistor forms a first pin of the reference voltage unit, a common end formed by connecting a B pin of the voltage stabilizing chip with the first pin of the first resistor is connected with the first pin of the first capacitor, a common end formed by connecting a second pin of the first resistor with the first pin of the second resistor forms a fourth pin of the reference voltage unit, and a common end formed by connecting a second pin of the second resistor with a second pin of the first capacitor is connected with a GND pin of the voltage stabilizing chip to form a second pin of the reference voltage unit;
the fault detection unit comprises a voltage comparison chip, a first diode, a fourth resistor, a fifth resistor and a second capacitor, wherein the positive electrode of the first diode is connected with the LED+ signal output end of the LED driver constant current unit, the negative electrode of the first diode is connected with the first pin of the fifth resistor, the second pin of the fifth resistor is connected with the fifth pin of the voltage comparison chip, the first pin of the fourth resistor is connected with the LED-signal output end of the LED driver constant current unit, the common end formed by the connection of the second pin of the fourth resistor and the first pin of the second capacitor is connected with the third pin of the voltage comparison chip, the second pin of the second capacitor, the fourth pin of the voltage comparison chip, the second pin of the reference voltage unit and the GND end of the +5V voltage stabilizing unit are connected and grounded, the second pin of the voltage comparison chip is connected with the fourth pin of the voltage comparison chip, the common end of the voltage comparison chip is connected with the voltage of the fourth pin of the reference voltage comparison chip, and the voltage of the eighth pin of the voltage comparison chip is connected with the voltage comparison unit is connected with the voltage of the V end of the eighth pin of the voltage comparison unit;
the display module unit comprises a buzzer, a red indicator lamp, a yellow indicator lamp and a sixth resistor, wherein the anodes of the buzzer, the red indicator lamp and the yellow indicator lamp are connected to form a common end and are connected with the +5V output end of the +5V voltage stabilizing unit, the cathode of the red indicator lamp is connected with the first pin of the sixth resistor, and the second pin of the sixth resistor is grounded;
the display module driving unit comprises a first triode, a seventh resistor, an eighth resistor, a ninth resistor and a tenth resistor, wherein the base electrode of the first triode is connected with the first pin of the ninth resistor, the second pin of the ninth resistor is connected with the first pin of the tenth resistor, the second pin of the tenth resistor is connected with the negative electrode of the yellow indicator lamp, the collector electrode of the first triode is connected with the first pin of the seventh resistor, the second pin of the seventh resistor is grounded, the common end formed by connecting the emitter electrode of the first triode with the negative electrode of the buzzer is connected with the first pin of the eighth resistor, the second pin of the eighth resistor is connected with the +5V output end of the +5V voltage stabilizing unit, and the common end formed by connecting the first pin of the voltage comparison chip with the seventh pin is connected with the common end formed by connecting the ninth resistor with the tenth resistor;
the overcurrent protection unit comprises a wire winding fuse resistor, the rectifying and filtering unit comprises a rectifying bridge and a third capacitor, a first pin of the wire winding fuse resistor is connected with a commercial power alternating current end, a second pin of the wire winding fuse resistor is connected with the first pin of the rectifying bridge, the second pin of the rectifying bridge is connected with the commercial power alternating current end, a common end formed by connecting the third pin of the rectifying bridge with the first pin of the third capacitor is connected with a V+ signal input end of the +5V voltage stabilizing unit, and a common end formed by connecting the fourth pin of the rectifying bridge with the second pin of the third capacitor is connected with a V-signal input end of the +5V voltage stabilizing unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811633015.6A CN109587890B (en) | 2018-12-29 | 2018-12-29 | Driver circuit of LED lamp |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811633015.6A CN109587890B (en) | 2018-12-29 | 2018-12-29 | Driver circuit of LED lamp |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109587890A CN109587890A (en) | 2019-04-05 |
| CN109587890B true CN109587890B (en) | 2024-03-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811633015.6A Active CN109587890B (en) | 2018-12-29 | 2018-12-29 | Driver circuit of LED lamp |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100457878B1 (en) * | 2003-05-22 | 2004-11-18 | 김용호 | Ballast Circuit for LED Lamp |
| CN201499348U (en) * | 2009-08-18 | 2010-06-02 | 重庆师范大学 | LED illumination driving circuit with wide load and high efficiency |
| CN101720154A (en) * | 2009-12-15 | 2010-06-02 | 海洋王照明科技股份有限公司 | Emergency power supply switching circuit and LED drive circuit thereof |
| CN106332361A (en) * | 2016-09-20 | 2017-01-11 | 浙江阳光美加照明有限公司 | Frequency-flicker-free LED filament lamp |
| CN209930557U (en) * | 2018-12-29 | 2020-01-10 | 浙江阳光城市照明工程有限公司 | Driver circuit of LED lamp |
-
2018
- 2018-12-29 CN CN201811633015.6A patent/CN109587890B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100457878B1 (en) * | 2003-05-22 | 2004-11-18 | 김용호 | Ballast Circuit for LED Lamp |
| CN201499348U (en) * | 2009-08-18 | 2010-06-02 | 重庆师范大学 | LED illumination driving circuit with wide load and high efficiency |
| CN101720154A (en) * | 2009-12-15 | 2010-06-02 | 海洋王照明科技股份有限公司 | Emergency power supply switching circuit and LED drive circuit thereof |
| CN106332361A (en) * | 2016-09-20 | 2017-01-11 | 浙江阳光美加照明有限公司 | Frequency-flicker-free LED filament lamp |
| CN209930557U (en) * | 2018-12-29 | 2020-01-10 | 浙江阳光城市照明工程有限公司 | Driver circuit of LED lamp |
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| Publication number | Publication date |
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| CN109587890A (en) | 2019-04-05 |
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