CN215934713U - Low-cost constant current output drive circuit - Google Patents
Low-cost constant current output drive circuit Download PDFInfo
- Publication number
- CN215934713U CN215934713U CN202121784263.8U CN202121784263U CN215934713U CN 215934713 U CN215934713 U CN 215934713U CN 202121784263 U CN202121784263 U CN 202121784263U CN 215934713 U CN215934713 U CN 215934713U
- Authority
- CN
- China
- Prior art keywords
- resistor
- electrically connected
- pin
- unit
- voltage
- 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.)
- Active
Links
Images
Landscapes
- Continuous-Control Power Sources That Use Transistors (AREA)
Abstract
The utility model discloses a low-cost constant current output driving circuit, which comprises an input terminal, a voltage stabilizing unit, a feedback unit, an MOS (metal oxide semiconductor) tube unit and an output terminal, wherein the input terminal is connected with the output terminal; the input terminal is electrically connected with the voltage stabilizing unit and is used for inputting voltage; the voltage stabilizing unit is electrically connected with the feedback unit and is used for outputting stable voltage; the feedback unit is electrically connected with the MOS tube unit and used for outputting a feedback signal; the MOS tube unit is electrically connected with the output terminal; the application aims at providing a low-cost constant current output drive circuit, can output constant current, avoids destroying components and parts.
Description
Technical Field
The utility model relates to the technical field of integrated circuit design, in particular to a low-cost constant current output driving circuit.
Background
At present, in a driving circuit, especially in some small-sized displays, due to the reasons of cost and scheme architecture, many backlight driving circuits adopt a simple driving IC to make multi-channel backlight, and all output branch circuits are forced to operate in parallel, and this operating mode can cause the operating currents of the branch circuits to be non-uniform, taking two branch circuits as an example, if the currents of the two branch circuits are 300mA, when the currents of the two branch circuits generate non-uniform currents, one branch circuit may be 100mA, and the other branch circuit may reach 500mA, and the branch circuit with large current is easy to burn out, which is fatal to the quality and safety of the display.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a low-cost constant current output driving circuit which can output constant current and avoid damaging components.
In order to achieve the purpose, the utility model adopts the following technical scheme: a low-cost constant current output drive circuit comprises an input terminal, a voltage stabilizing unit, a feedback unit, an MOS tube unit and an output terminal; the input terminal is electrically connected with the voltage stabilizing unit and is used for inputting voltage; the voltage stabilizing unit is electrically connected with the feedback unit and is used for outputting stable voltage; the feedback unit is electrically connected with the MOS tube unit and used for outputting a feedback signal; the MOS tube unit is electrically connected with the output terminal.
Preferably, the voltage stabilizing unit comprises a resistor R20, a voltage stabilizer, a resistor R24 and a capacitor C6; one end of the resistor R20 is electrically connected with the input terminal, the other end of the resistor R20 is electrically connected with the first pin and the third pin of the voltage stabilizer, the second pin of the voltage stabilizer is electrically connected with one end of the resistor R24, the other end of the resistor R24 is grounded, and the capacitor C6 is connected between the first pin and the second pin of the voltage stabilizer in parallel.
Preferably, the voltage stabilizer is of the type TL 431.
Preferably, the feedback unit comprises a resistor R21, an operational amplifier, a resistor R22 and a capacitor C5; the one end of resistance R21 with the first pin electricity of stabiliser is connected, the other end of resistance R21 with operational amplifier's positive input end electricity is connected, operational amplifier's negative input end with the second pin electricity of stabiliser is connected, operational amplifier's fourth pin ground connection, operational amplifier's eleventh pin connects positive 5V power, operational amplifier's output with the one end electricity of resistance R22 is connected, the other end of resistance R22 with MOS pipe unit electricity is connected, electric capacity C5 connects in parallel at the both ends of resistance R22.
Preferably, the MOS transistor unit includes a MOS transistor and a resistor R23, a first pin of the MOS transistor is electrically connected to the other end of the resistor R22, a second pin of the MOS transistor is electrically connected to the other end of the resistor R21, a third pin of the MOS transistor is electrically connected to one end of the resistor R23, and the other end of the resistor R23 is electrically connected to the output terminal.
The technical scheme of the utility model has the beneficial effects that: through input terminal, voltage stabilizing unit, feedback unit, MOS pipe unit and output terminal cooperation, adopt feedback unit and MOS pipe unit direct drive load circuit, utilize voltage stabilizing circuit's three-terminal adjustability, form stable voltage output. When different voltages are input, the connection method of the voltage stabilizing unit and the virtual short virtual disconnection of the feedback unit can directly calculate the output current, so that the output terminal can output constant current.
Drawings
FIG. 1 is a schematic circuit diagram of one embodiment of the present invention.
Wherein: input terminal 1, voltage regulation unit 2, feedback unit 3, MOS pipe unit 4, output terminal 5.
Detailed Description
The technical scheme of the utility model is further explained by the specific implementation mode in combination with the attached drawings.
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.
In the description of the present invention, "a plurality" means two or more unless otherwise specified.
Referring to fig. 1, a low-cost constant current output driving circuit includes an input terminal 1, a voltage stabilizing unit 2, a feedback unit 3, a MOS transistor unit 4, and an output terminal 5; the input terminal 1 is electrically connected with the voltage stabilizing unit 2 and is used for inputting voltage; the voltage stabilizing unit 2 is electrically connected with the feedback unit 3, and the voltage stabilizing unit 2 is used for outputting stable voltage; the feedback unit 3 is electrically connected with the MOS tube unit 4 and is used for outputting a feedback signal; the MOS transistor unit 4 is electrically connected to an output terminal 5.
Preferably, the voltage stabilizing unit 2 comprises a resistor R20, a voltage stabilizer, a resistor R24 and a capacitor C6; one end of the resistor R20 is electrically connected with the input terminal 1, the other end of the resistor R20 is electrically connected with the first pin and the third pin of the voltage stabilizer, the second pin of the voltage stabilizer is electrically connected with one end of the resistor R24, the other end of the resistor R24 is grounded, and the capacitor C6 is connected between the first pin and the second pin of the voltage stabilizer in parallel. The model adopted by the voltage stabilizer is TL 431.
Specifically, the feedback unit 3 includes a resistor R21, an operational amplifier, a resistor R22, and a capacitor C5; the one end of resistance R21 with the first pin electricity of stabiliser is connected, the other end of resistance R21 with operational amplifier's positive input end electricity is connected, operational amplifier's negative input end with the second pin electricity of stabiliser is connected, operational amplifier's fourth pin ground connection, operational amplifier's eleventh pin connects positive 5V power, operational amplifier's output with the one end electricity of resistance R22 is connected, the other end of resistance R22 with MOS pipe unit 4 electricity is connected, electric capacity C5 connects in parallel at the both ends of resistance R22.
Preferably, the MOS transistor unit 4 includes a MOS transistor and a resistor R23, a first pin of the MOS transistor is electrically connected to the other end of the resistor R22, a second pin of the MOS transistor is electrically connected to the other end of the resistor R21, a third pin of the MOS transistor is electrically connected to one end of the resistor R23, and the other end of the resistor R23 is electrically connected to the output terminal 5.
The application adopts an operational amplifier as a feedback MOS tube direct drive load circuit, a resistor R20 is directly connected in series with a first pin and a third pin of a voltage stabilizer TL431 at an input terminal P3, the adjustability of three ends of the voltage stabilizer TL431 is utilized to match with another resistor R24 to be directly connected with GND to form a stable voltage to be output at the first pin, the stable voltage provided by the voltage stabilizer is directly supplied to a second pin of a negative input end of the operational amplifier, C6 plays a role of charging and discharging, a current limiting resistor R21 is directly connected in series with the first pin and the third pin of the voltage stabilizer TL431, a resistor R21 is directly connected in series with a drain electrode of the MOS tube at an output end, the output end of the operational amplifier is directly connected in series with a resistor to the MOS, the source electrode of the MOS tube is directly connected with a resistor to be connected with a current meter to be directly connected with the GND, when different voltages are input, due to the connection method of the voltage stabilizer GND, the output current is 2.48V/R21 by adding the virtual break virtual short of the operational amplifier, so that the circuit for controlling the output end can be kept in a constant current state.
In the description herein, references to the description of the terms "embodiment," "example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The technical principle of the present invention is described above in connection with specific embodiments. The description is made for the purpose of illustrating the principles of the utility model and should not be construed in any way as limiting the scope of the utility model. Based on the explanations herein, those skilled in the art will be able to conceive of other embodiments of the present invention without inventive effort, which would fall within the scope of the present invention.
Claims (5)
1. A low-cost constant current output drive circuit is characterized by comprising an input terminal, a voltage stabilizing unit, a feedback unit, an MOS (metal oxide semiconductor) tube unit and an output terminal; the input terminal is electrically connected with the voltage stabilizing unit and is used for inputting voltage; the voltage stabilizing unit is electrically connected with the feedback unit and is used for outputting stable voltage; the feedback unit is electrically connected with the MOS tube unit and used for outputting a feedback signal; the MOS tube unit is electrically connected with the output terminal.
2. The low-cost constant-current output driving circuit according to claim 1, wherein the voltage stabilizing unit comprises a resistor R20, a voltage stabilizer, a resistor R24 and a capacitor C6; one end of the resistor R20 is electrically connected with the input terminal, the other end of the resistor R20 is electrically connected with the first pin and the third pin of the voltage stabilizer, the second pin of the voltage stabilizer is electrically connected with one end of the resistor R24, the other end of the resistor R24 is grounded, and the capacitor C6 is connected between the first pin and the second pin of the voltage stabilizer in parallel.
3. The low-cost constant-current output driving circuit as claimed in claim 2, wherein the voltage regulator is of type TL 431.
4. A low-cost constant current output driving circuit according to claim 2, wherein the feedback unit includes a resistor R21, an operational amplifier, a resistor R22 and a capacitor C5; the one end of resistance R21 with the first pin electricity of stabiliser is connected, the other end of resistance R21 with operational amplifier's positive input end electricity is connected, operational amplifier's negative input end with the second pin electricity of stabiliser is connected, operational amplifier's fourth pin ground connection, operational amplifier's eleventh pin connects positive 5V power, operational amplifier's output with the one end electricity of resistance R22 is connected, the other end of resistance R22 with MOS pipe unit electricity is connected, electric capacity C5 connects in parallel at the both ends of resistance R22.
5. The low-cost constant current output driving circuit as claimed in claim 4, wherein the MOS transistor unit comprises a MOS transistor and a resistor R23, a first pin of the MOS transistor is electrically connected with the other end of the resistor R22, a second pin of the MOS transistor is electrically connected with the other end of the resistor R21, a third pin of the MOS transistor is electrically connected with one end of the resistor R23, and the other end of the resistor R23 is electrically connected with the output terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121784263.8U CN215934713U (en) | 2021-08-02 | 2021-08-02 | Low-cost constant current output drive circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121784263.8U CN215934713U (en) | 2021-08-02 | 2021-08-02 | Low-cost constant current output drive circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215934713U true CN215934713U (en) | 2022-03-01 |
Family
ID=80398055
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121784263.8U Active CN215934713U (en) | 2021-08-02 | 2021-08-02 | Low-cost constant current output drive circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215934713U (en) |
-
2021
- 2021-08-02 CN CN202121784263.8U patent/CN215934713U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103454572B (en) | Battery analogue circuit | |
| CN117394507B (en) | Intelligent charger for optimizing service life of battery and control circuit thereof | |
| CN101135917A (en) | Voltage regulator | |
| CN105762781A (en) | Surge current control circuit and power supply device | |
| CN215934713U (en) | Low-cost constant current output drive circuit | |
| CN100414810C (en) | Voltage identification short circuit protection constant current voltage stabilizing circuit | |
| CN203616686U (en) | Quick start circuit of integrated circuit and constant current drive circuit | |
| CN206877188U (en) | Low-power dissipation power supply power supply circuit | |
| CN203026929U (en) | Spark limiting device of intrinsically safe power supply | |
| CN201497922U (en) | Constant current protective device | |
| CN217406174U (en) | Overpower protection circuit of LED driving power supply | |
| CN218825334U (en) | Adjustable constant current circuit based on three-terminal regulator | |
| CN213027530U (en) | Dual-power supply circuit and dual-power supply device | |
| CN218276132U (en) | OVP high-side overvoltage protection circuit | |
| CN100553101C (en) | Power circuit | |
| CN217240585U (en) | Buffer circuit with load power-on impact current suppression function | |
| CN212435349U (en) | Lithium battery overcurrent protection circuit | |
| CN219181173U (en) | Overcurrent protection module capable of interactively setting overcurrent threshold | |
| CN211981537U (en) | Current-compatible charging circuit and charger | |
| CN207281637U (en) | Regulator circuit plate | |
| CN216774607U (en) | 48V safety drive circuit based on logic gate | |
| CN218678835U (en) | Quick start circuit and electronic equipment | |
| CN210865629U (en) | Power supply protection structure for solid-state storage device | |
| CN214704460U (en) | Constant current loading circuit | |
| CN107168432A (en) | Low-power dissipation power supply power supply circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |