CN110784967A - LED drive circuit - Google Patents
LED drive circuit Download PDFInfo
- Publication number
- CN110784967A CN110784967A CN201910997370.XA CN201910997370A CN110784967A CN 110784967 A CN110784967 A CN 110784967A CN 201910997370 A CN201910997370 A CN 201910997370A CN 110784967 A CN110784967 A CN 110784967A
- Authority
- CN
- China
- Prior art keywords
- resistor
- electrode
- tube
- operational amplifier
- pmos
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Landscapes
- Circuit Arrangement For Electric Light Sources In General (AREA)
- Led Devices (AREA)
Abstract
The invention discloses an LED drive circuit. An LED driving circuit comprises a first resistor, a second resistor, a first operational amplifier, a first NMOS (N-channel metal oxide semiconductor) tube, a first PNP (plug-and-play) tube, a first PMOS (P-channel metal oxide semiconductor) tube, a second PMOS tube, a third resistor and an LED lamp. The LED driving circuit provided by the invention can more reliably drive the LED for illumination, and obtains stable driving current.
Description
Technical Field
The invention relates to the technical field of electronics, in particular to an LED driving circuit.
Background
In order to drive LEDs more reliably for illumination, a stable drive current is required, otherwise damage to the LEDs, and thus the entire circuit, can result.
Disclosure of Invention
The invention aims to solve the defects of the prior art and provides an LED driving circuit.
The utility model provides a LED drive circuit, includes first resistance, second resistance, first operational amplifier, first NMOS pipe, first PNP pipe, first PMOS pipe, second PMOS pipe, third resistance and LED lamp:
one end of the first resistor is connected with a power supply voltage VCC, and the other end of the first resistor is connected with one end of the second resistor and the positive input end of the first operational amplifier; one end of the second resistor is connected to one end of the first resistor and the positive input end of the first operational amplifier. The other end is grounded; the positive input end of the first operational amplifier is connected with one end of the first resistor and one end of the second resistor, the negative input end of the first operational amplifier is connected with the source electrode of the first NMOS tube and the emitting electrode of the first PNP tube, and the output end of the first operational amplifier is connected with the grid electrode of the first NMOS tube; the grid electrode of the first NMOS tube is connected with the output end of the first operational amplifier, the drain electrode is connected with the grid electrode and the drain electrode of the first PMOS tube and the grid electrode of the second PMOS tube, and the source electrode is connected with the negative input end of the first operational amplifier and the emitter electrode of the first PNP tube; the base electrode of the first PNP tube is grounded, the collector electrode of the first PNP tube is grounded, and the emitter electrode of the first PNP tube is connected with the negative input end of the first operational amplifier and the source electrode of the first NMOS tube; the grid electrode and the drain electrode of the first PMOS tube are connected together and then connected with the drain electrode of the first NMOS tube and the grid electrode of the second PMOS tube, and the source electrode is connected with a power supply voltage VCC; the grid electrode of the second PMOS tube is connected with the drain electrode of the first NMOS tube and the grid electrode and the drain electrode of the first PMOS tube, the drain electrode is connected with one end of the third resistor, and the source electrode is connected with a power supply voltage VCC; one end of the third resistor is connected with the drain electrode of the second PMOS tube, and the other end of the third resistor is connected with the P electrode of the LED lamp; and the P electrode of the LED lamp is connected with one end of the third resistor, and the other end of the third resistor is grounded.
The first resistor and the second resistor form a voltage division circuit to obtain a voltage VA at a point A; the first operational amplifier and the first NMOS tube form a follower, A voltage VA is added to a diode formed by the first PNP tube to generate current, and then the current is mirrored to the second PMOS tube through the first PMOS tube to drive the LED lamp; the third resistor plays a role in limiting current.
Drawings
Fig. 1 is a circuit diagram of an LED driving circuit of the present invention.
Detailed Description
The present invention will be further explained with reference to the accompanying drawings.
An LED driving circuit, as shown in fig. 1, includes a first resistor 101, a second resistor 102, a first operational amplifier 103, a first NMOS transistor 104, a first PNP transistor 105, a first PMOS transistor 106, a second PMOS transistor 107, a third resistor 108, and an LED lamp 109:
one end of the first resistor 101 is connected to a power supply voltage VCC, and the other end is connected to one end of the second resistor 102 and a positive input end of the first operational amplifier 103; one end of the second resistor 102 is connected to one end of the first resistor 101 and the positive input end of the first operational amplifier 103. The other end is grounded; a positive input end of the first operational amplifier 103 is connected with one end of the first resistor 101 and one end of the second resistor 102, a negative input end is connected with a source electrode of the first NMOS tube 104 and an emitter electrode of the first PNP tube 105, and an output end is connected with a gate electrode of the first NMOS tube 104; the gate of the first NMOS transistor 104 is connected to the output terminal of the first operational amplifier 103, the drain is connected to the gate and drain of the first PMOS transistor 106 and the gate of the second PMOS transistor 107, and the source is connected to the negative input terminal of the first operational amplifier 103 and the emitter of the first PNP transistor 105; the base electrode of the first PNP transistor 105 is connected, the collector electrode is grounded, and the emitter electrode is connected to the negative input end of the first operational amplifier 103 and the source electrode of the first NMOS transistor 104; the grid and the drain of the first PMOS transistor 106 are connected together and then connected with the drain of the first NMOS transistor 104 and the grid of the second PMOS transistor 107, and the source is connected with a power supply voltage VCC; the grid electrode of the second PMOS transistor 107 is connected with the drain electrode of the first NMOS transistor 104 and the grid electrode and the drain electrode of the first PMOS transistor 106, the drain electrode is connected with one end of the third resistor 108, and the source electrode is connected with a power supply voltage VCC; one end of the third resistor 108 is connected to the drain of the second PMOS transistor 107, and the other end is connected to the P-pole of the LED lamp 109; the P pole of the LED lamp 109 is connected to one end of the third resistor 108, and the other end is grounded.
The first resistor 101 and the second resistor 102 form a voltage division circuit to obtain a voltage VA at a point A; the first operational amplifier 103 and the first NMOS transistor 104 form a follower, and the a voltage VA is applied to the diode formed by the first PNP transistor 105 to generate a current, and then the current is mirrored to the second PMOS transistor 107 through the first PMOS transistor 106 to drive the LED lamp 109; the third resistor 108 functions as a current limiting.
The description of the embodiments provided above is merely illustrative of preferred embodiments of the present invention, and it will be apparent to those skilled in the art that the present invention can be implemented or used in light of the above description. It should be noted that, for those skilled in the art, it is possible to make several modifications and variations without departing from the technical principle of the present invention, and any invention that does not depart from the scope of the essential spirit of the present invention should be construed as the scope of the present invention.
Claims (2)
1. An LED drive circuit, characterized by: comprises a first resistor, a second resistor, a first operational amplifier, a first resistor
The LED lamp comprises an NMOS (N-channel metal oxide semiconductor) tube, a first PNP (plug-and-play) tube, a first PMOS (P-channel metal oxide semiconductor) tube, a second PMOS tube, a third resistor and an LED lamp;
one end of the first resistor is connected with a power supply voltage VCC, and the other end of the first resistor is connected with one end of the second resistor and the positive input end of the first operational amplifier; one end of the second resistor is connected to one end of the first resistor and the positive input end of the first operational amplifier.
2. The other end is grounded; the positive input end of the first operational amplifier is connected with one end of the first resistor and one end of the second resistor, the negative input end of the first operational amplifier is connected with the source electrode of the first NMOS tube and the emitting electrode of the first PNP tube, and the output end of the first operational amplifier is connected with the grid electrode of the first NMOS tube; the grid electrode of the first NMOS tube is connected with the output end of the first operational amplifier, the drain electrode is connected with the grid electrode and the drain electrode of the first PMOS tube and the grid electrode of the second PMOS tube, and the source electrode is connected with the negative input end of the first operational amplifier and the emitter electrode of the first PNP tube; the base electrode of the first PNP tube is grounded, the collector electrode of the first PNP tube is grounded, and the emitter electrode of the first PNP tube is connected with the negative input end of the first operational amplifier and the source electrode of the first NMOS tube; the grid electrode and the drain electrode of the first PMOS tube are connected together and then connected with the drain electrode of the first NMOS tube and the grid electrode of the second PMOS tube, and the source electrode is connected with a power supply voltage VCC; the grid electrode of the second PMOS tube is connected with the drain electrode of the first NMOS tube and the grid electrode and the drain electrode of the first PMOS tube, the drain electrode is connected with one end of the third resistor, and the source electrode is connected with a power supply voltage VCC; one end of the third resistor is connected with the drain electrode of the second PMOS tube, and the other end of the third resistor is connected with the P electrode of the LED lamp; and the P electrode of the LED lamp is connected with one end of the third resistor, and the other end of the third resistor is grounded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910997370.XA CN110784967A (en) | 2019-10-21 | 2019-10-21 | LED drive circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910997370.XA CN110784967A (en) | 2019-10-21 | 2019-10-21 | LED drive circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110784967A true CN110784967A (en) | 2020-02-11 |
Family
ID=69385975
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910997370.XA Withdrawn CN110784967A (en) | 2019-10-21 | 2019-10-21 | LED drive circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110784967A (en) |
-
2019
- 2019-10-21 CN CN201910997370.XA patent/CN110784967A/en not_active Withdrawn
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102638918A (en) | Light emitting diode driving device | |
| CN111130532A (en) | IGBT gate push-pull driving circuit and method and IGBT driving circuit | |
| CN103324232B (en) | Reference voltage circuit | |
| CN102595695B (en) | Indicator drive circuit | |
| CN103440011B (en) | Linear constant-current-source circuit having voltage difference compensation | |
| CN104170099A (en) | Led drive circuit | |
| KR101413878B1 (en) | Apparatus for driving lighting system using Light Emitting Diode | |
| CN110784967A (en) | LED drive circuit | |
| CN214591137U (en) | MOS tube driving bleeder circuit of switching power supply | |
| CN110048680B (en) | Low-dropout high-power composite PMOS (P-channel metal oxide semiconductor) tube equivalent circuit | |
| CN109121255B (en) | Control circuit for controlling operation of two LED lamps by using single IO port | |
| CN110769550A (en) | LED drive circuit | |
| CN111278184A (en) | LED lighting driving circuit | |
| CN110784963A (en) | LED driving device | |
| CN203951643U (en) | A kind of LED constant-current drive circuit | |
| CN204615787U (en) | A kind of 0 ~ 28V step voltage generator | |
| CN111263481A (en) | LED driving device | |
| CN110740538A (en) | LED lighting driving circuit | |
| CN204598363U (en) | A kind of constant current driving device | |
| CN110707786A (en) | Charging circuit | |
| CN110708057A (en) | Three-state gate | |
| CN110635540A (en) | Battery charging device | |
| CN214125579U (en) | LED amplifying unit and dimming drive circuit comprising same | |
| CN109348572A (en) | LED drive circuit | |
| CN214544866U (en) | Constant voltage light-dimming MOS tube driving circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| WW01 | Invention patent application withdrawn after publication | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20200211 |