CN216390799U - Adjustable step-down driving circuit - Google Patents
Adjustable step-down driving circuit Download PDFInfo
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- CN216390799U CN216390799U CN202122170092.6U CN202122170092U CN216390799U CN 216390799 U CN216390799 U CN 216390799U CN 202122170092 U CN202122170092 U CN 202122170092U CN 216390799 U CN216390799 U CN 216390799U
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- 239000003990 capacitor Substances 0.000 claims abstract description 14
- 238000012423 maintenance Methods 0.000 abstract description 2
- 229910044991 metal oxide Inorganic materials 0.000 abstract 1
- 150000004706 metal oxides Chemical class 0.000 abstract 1
- 239000004065 semiconductor Substances 0.000 abstract 1
- 230000002159 abnormal effect Effects 0.000 description 3
- 238000005070 sampling Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
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Abstract
The utility model discloses an adjustable step-down driving circuit which comprises an adjustable reference voltage module, an operational amplifier IC1, a PMOS (P-channel metal oxide semiconductor) tube Q1 and a capacitor C1, wherein the output end of the adjustable reference voltage module is connected to the inverting input end of the operational amplifier IC1, the non-inverting input end of the operational amplifier IC1 is connected to the positive pole of a power output end, the output end of the operational amplifier IC1 is connected to the grid of the PMOS tube Q1, the source electrode of the PMOS tube Q1 is connected with the positive pole of the power input end, and the drain electrode of the PMOS tube Q1 is connected with the positive pole of the power output end and the capacitor C1 and is grounded through the other end of the capacitor C1. The utility model has simple circuit, simple assembly, convenient maintenance and adjustment, adjustable output voltage, good practicability and easy realization on a PCB board with small space.
Description
Technical Field
The utility model relates to the technical field of voltage reduction of a driving circuit, in particular to an adjustable voltage reduction driving circuit.
Background
The Drive Circuit (Drive Circuit) is an intermediate Circuit located between the main Circuit and the control Circuit and used for amplifying a signal of the control Circuit (i.e., amplifying a signal of the control Circuit so that the signal can Drive the power transistor). In daily life, because various control circuits have different requirements on voltage, the voltage output by a driving circuit is generally subjected to voltage boosting or voltage reducing conversion. With regard to the step-down driving circuit, among the current step-down driving circuit, its output voltage value is mostly fixed, and the electronic components that partial step-down driving circuit used are more moreover, and the circuit of design is comparatively complicated, not only inconvenient regulation and modification, and the space that occupies PCB is also great, therefore need design an adjustable step-down driving circuit that the structure is comparatively simple, the subassembly is comparatively retrencied.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide an adjustable buck driving circuit with more simplified components.
In order to achieve the purpose, the technical scheme adopted by the utility model is as follows:
the utility model provides an adjustable step-down drive circuit, includes adjustable reference voltage module, operational amplifier IC1, PMOS pipe Q1 and electric capacity C1, the output of adjustable reference voltage module is connected to operational amplifier IC 1's inverting input, operational amplifier IC 1's homophase input is connected to the power output positive pole, and the output is connected to PMOS pipe Q1 grid, PMOS pipe Q1's source is connected with the power input positive pole, and the drain electrode is connected with power output positive pole, electric capacity C1 to other end ground connection through electric capacity C1.
Further, the power supply further comprises a voltage dividing resistor R1 and a voltage dividing resistor R2, wherein the non-inverting input end of the operational amplifier IC1 is respectively connected with the voltage dividing resistor R1 and the voltage dividing resistor R2, the non-inverting input end of the operational amplifier IC1 is connected to the anode of the power supply output end through the other end of the voltage dividing resistor R1, and the other end of the operational amplifier IC is connected to the cathode of the power supply output end through the other end of the voltage dividing resistor R2. The non-inverting input terminal of the operational amplifier IC1 can be supplied with a proper sampling voltage by adjusting the voltage dividing resistor R1 and the voltage dividing resistor R2.
Further, the adjustable reference voltage module comprises an adjustable three-terminal regulator IC2, a current-limiting resistor R3, a voltage-dividing resistor R4 and a voltage-dividing resistor R5, wherein an anode of the adjustable three-terminal regulator IC2 is grounded, a cathode of the adjustable three-terminal regulator IC2 is connected to the anode of the power input end after being connected in series with the current-limiting resistor R3, a reference electrode of the adjustable three-terminal regulator IC2 is in short circuit with the cathode of the adjustable three-terminal regulator IC, two ends of the adjustable three-terminal regulator IC 4 are connected to the cathode and the anode of the adjustable three-terminal regulator IC2 after being connected in series with the voltage-dividing resistor R5, and a connection node of the voltage-dividing resistor R4 and the voltage-dividing resistor R5 is used as an output end of the adjustable reference voltage module. The current limiting resistor R3 can prevent the current entering the adjustable three-terminal regulator IC2 from being overlarge to cause abnormal work of the adjustable three-terminal regulator IC2, a stable voltage can be provided by short circuit of a reference electrode and a cathode on the adjustable three-terminal regulator IC2, and an adjustable reference voltage can be provided for the operational amplifier IC1 by matching with the adjustment of the voltage dividing resistor R4 and the voltage dividing resistor R5.
Further, the model of the adjustable three-terminal regulator IC2 is TL 431.
Furthermore, the positive power pin of the operational amplifier IC1 is connected to the positive terminal of the power input terminal through the current limiting resistor R6, and the negative power pin is grounded. The current limiting resistor R6 is provided to prevent the current into the operational amplifier IC1 from being too large to cause an abnormal operation.
Further, the device also comprises a capacitor C2, wherein the capacitor C2 is connected in parallel with the positive pole and the negative pole of the power input end.
Further, the operational amplifier IC1 is model LM 358.
The utility model has the following beneficial effects: 1. the sampled voltage of the power output end is compared with the reference voltage provided by the adjustable reference voltage module through the operational amplifier IC1, and the closed PMOS tube Q1 is continuously opened and closed according to the comparison result, so that the output voltage is adjusted, the circuit of the whole voltage reduction driving circuit is simple, the assembly is simplified, and the maintenance and the adjustment are convenient; 2. the PCB is easy to arrange and is more easily realized on a PCB with small space; 3. the output voltage after the voltage reduction and conversion can be flexibly adjusted, and the practicability is good.
Drawings
FIG. 1 is a schematic view of the structure of the present invention.
Description of the main component symbols: 1. and the adjustable reference voltage module.
Detailed Description
The utility model is further described with reference to the following drawings and detailed description.
As shown in fig. 1, an adjustable buck driving circuit includes an adjustable reference voltage module 1, an operational amplifier IC1, a PMOS transistor Q1 and a capacitor C1, an output terminal of the adjustable reference voltage module 1 is connected to an inverting input terminal of the operational amplifier IC1, a non-inverting input terminal of the operational amplifier IC1 is connected to a positive pole of a power output terminal OUT DC, an output terminal is connected to a gate of the PMOS transistor Q1, a source of the PMOS transistor Q1 is connected to a positive pole of the power input terminal INP DC, and a drain is connected to the positive pole of the power output terminal OUT DC and the capacitor C1, and is grounded through another end of the capacitor C1.
The power supply circuit further comprises a voltage dividing resistor R1 and a voltage dividing resistor R2, wherein the non-inverting input end of the operational amplifier IC1 is respectively connected with the voltage dividing resistor R1 and the voltage dividing resistor R2, the other end of the voltage dividing resistor R1 is connected to the positive pole of the power output end OUT DC, and the other end of the voltage dividing resistor R2 is connected to the negative pole of the power output end OUT DC.
The adjustable reference voltage module 1 comprises an adjustable three-terminal regulator IC2, a current-limiting resistor R3, a voltage-dividing resistor R4 and a voltage-dividing resistor R5, the anode of the adjustable three-terminal regulator IC2 is grounded, the cathode of the adjustable three-terminal regulator IC2 is connected to the INP DC anode of the power input end after being connected with the current-limiting resistor R3 in series, the reference electrode is in short circuit with the cathode, the two ends of the voltage-dividing resistor R4 are connected with the cathode and the anode of the adjustable three-terminal regulator IC2 after being connected with the voltage-dividing resistor R5 in series, and the connecting node of the voltage-dividing resistor R4 and the voltage-dividing resistor R5 is used as the output end of the adjustable reference voltage module 1. The model number of the adjustable three-terminal regulator IC2 is TL 431.
The positive power pin of the operational amplifier IC1 is connected to the positive terminal of the power input INP DC through a current limiting resistor R6, and the negative power pin is grounded. The capacitor C2 is further included, and the capacitor C2 is connected in parallel with the positive and negative poles of the power input terminal INP DC. Operational amplifier IC1 is model LM 358.
In the drive circuit, a TL431 chip is used as an adjustable three-terminal regulator IC2, a reference electrode of the TL is in short circuit with a cathode to provide stable 2.495V voltage, the TL431 chip is connected to an inverting input end of an operational amplifier IC1 after being adjusted and controlled by a divider resistor R4 and a divider resistor R5 to provide adjustable reference voltage for the operational amplifier IC1, the divider resistor R1 and the divider resistor R2 are adjusted to input sampling voltage to a non-inverting input end of the operational amplifier IC1, the sampling voltage and the reference voltage are compared by the operational amplifier IC1, whether the output voltage value of the OUT DC of the power output end is higher or lower than a set output voltage value can be judged, when the output voltage value is higher, the operational amplifier IC1 outputs high level, a PMOS tube Q1 is cut off, when the output voltage is lower, the operational amplifier IC1 outputs low level, a PMOS tube Q1 is conducted, and the judgment, comparison, and comparison, judgment, and comparison, continuous, And the PMOS tube Q1 is turned on and off, and the capacitor C1 and the capacitor C2 are combined to filter and store energy, so that stable output voltage meeting the requirements can be obtained. In addition, the driving circuit is additionally provided with a current limiting resistor R3 and a current limiting resistor R6, so that the abnormal operation caused by overlarge current entering the adjustable three-terminal regulator IC2 and the operational amplifier IC1 can be prevented.
The driving circuit is simple in circuit, simple in assembly, convenient to maintain and adjust, small in occupied space and easy to achieve on a PCB in a small space. The output voltage value can be adjusted by controlling the voltage dividing resistor R1, the voltage dividing resistor R2, the voltage dividing resistor R4 and the voltage dividing resistor R5, and the practicability is good.
While the utility model has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the utility model as defined by the appended claims.
Claims (7)
1. An adjustable step-down driving circuit is characterized in that: including adjustable reference voltage module, operational amplifier IC1, PMOS pipe Q1 and electric capacity C1, the output of adjustable reference voltage module is connected to operational amplifier IC 1's inverting input, operational amplifier IC 1's in-phase input end is connected to power output OUT DC anodal, and the output is connected to PMOS pipe Q1 grid, PMOS pipe Q1's source is connected with power input INP DC anodal, and the drain electrode is connected with power output positive pole, electric capacity C1 to other end ground connection through electric capacity C1.
2. An adjustable buck driver circuit as claimed in claim 1, wherein: still include divider resistance R1 and divider resistance R2, operational amplifier IC 1's non inverting input end is connected with divider resistance R1, divider resistance R2 respectively to be connected to the power output end positive pole through divider resistance R1's the other end, be connected to the power output end negative pole through divider resistance R2 the other end.
3. An adjustable buck driver circuit as claimed in claim 1, wherein: the adjustable reference voltage module comprises an adjustable three-terminal regulator IC2, a current-limiting resistor R3, a voltage-dividing resistor R4 and a voltage-dividing resistor R5, the anode of the adjustable three-terminal regulator IC2 is grounded, the cathode of the adjustable three-terminal regulator IC2 is connected to the anode of the power input end after being connected in series with the current-limiting resistor R3, the reference electrode of the adjustable three-terminal regulator IC2 is in short circuit with the cathode of the adjustable three-terminal regulator IC, the voltage-dividing resistor R4 is connected with the voltage-dividing resistor R5 at two ends after being connected in series, and the output end of the adjustable reference voltage module is taken as the connection node of the voltage-dividing resistor R4 and the voltage-dividing resistor R5.
4. An adjustable buck driver circuit as claimed in claim 3, wherein: the model of the adjustable three-terminal voltage regulator IC2 is TL 431.
5. An adjustable buck driver circuit as claimed in claim 1, wherein: and a positive power supply pin of the operational amplifier IC1 is connected to the positive electrode of the power supply input end through a current limiting resistor R6, and a negative power supply pin is grounded.
6. An adjustable buck driver circuit as claimed in claim 1, wherein: the capacitor C2 is also included, and the capacitor C2 is connected in parallel with the positive pole and the negative pole of the power input end.
7. An adjustable buck driver circuit as claimed in claim 1, wherein: the operational amplifier IC1 is model LM 358.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122170092.6U CN216390799U (en) | 2021-09-08 | 2021-09-08 | Adjustable step-down driving circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122170092.6U CN216390799U (en) | 2021-09-08 | 2021-09-08 | Adjustable step-down driving circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216390799U true CN216390799U (en) | 2022-04-26 |
Family
ID=81241268
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122170092.6U Active CN216390799U (en) | 2021-09-08 | 2021-09-08 | Adjustable step-down driving circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216390799U (en) |
-
2021
- 2021-09-08 CN CN202122170092.6U patent/CN216390799U/en active Active
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| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: 361000 Xiamen Torch High tech Zone (Xiang'an) Industrial Zone, Xianghai Second Road, Xiamen City, Fujian Province, China, Accelerator Phase III, Building 3 Patentee after: XIAMEN XUNHENG ELECTRONICS TECH Co.,Ltd. Country or region after: China Address before: Room 3047, Xuanye building, Chuangye Park, torch high tech Zone, Xiamen City, Fujian Province Patentee before: XIAMEN XUNHENG ELECTRONICS TECH Co.,Ltd. Country or region before: China |