CN214067261U - Temperature drift resistant overcurrent detection circuit and electronic equipment - Google Patents
Temperature drift resistant overcurrent detection circuit and electronic equipment Download PDFInfo
- Publication number
- CN214067261U CN214067261U CN202023169593.4U CN202023169593U CN214067261U CN 214067261 U CN214067261 U CN 214067261U CN 202023169593 U CN202023169593 U CN 202023169593U CN 214067261 U CN214067261 U CN 214067261U
- Authority
- CN
- China
- Prior art keywords
- resistor
- triode
- overcurrent detection
- circuit
- detection circuit
- 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
Abstract
The utility model discloses an anti-temperature drift overcurrent detection circuit and electronic equipment, which comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a first triode, a second triode, a narrow pulse width square wave circuit and a field effect tube; the drain of the field effect transistor is the input end of the overcurrent detection circuit, and the second end of the seventh resistor is the output end of the overcurrent detection circuit. The utility model discloses use simple component to realize overcurrent detection and prevent circuit overload's function, improved anti temperature drift characteristic, simplified circuit structure, the cost is reduced, improved the reliability.
Description
Technical Field
The utility model relates to a circuit monitoring technology field, concretely relates to anti temperature drift's overcurrent detection circuit and electronic equipment.
Background
The existing power output overcurrent protection is usually implemented by using an operational amplifier chip to build a linear amplification circuit to amplify a current signal with very low voltage, and when the current signal is greater than a certain value, a control chip is triggered to execute protection action.
The existing overcurrent protection circuit not only has limited application range due to large temperature drift, but also has complex circuit structure, high cost and low reliability.
SUMMERY OF THE UTILITY MODEL
To the defect among the prior art, the utility model provides an overcurrent detection circuit and electronic equipment of anti temperature drift, its aim at improves overcurrent detection circuit's anti temperature drift characteristic.
In a first aspect, an overcurrent detection circuit resistant to temperature drift comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a first triode, a second triode, a narrow pulse width square wave circuit and a field effect transistor; the drain electrode of the field effect tube is the input end of the overcurrent detection circuit, the grid electrode of the field effect tube is connected with the output end of the narrow pulse width square wave circuit, and the source electrode of the field effect tube is connected with the negative input end of the power supply of the narrow pulse width square wave circuit; the power supply positive input end of the narrow pulse width square wave circuit, the first end of the first resistor, the first end of the second resistor and the first end of the third resistor are connected with a high-voltage power supply; the trigger end of the narrow pulse width square wave circuit is respectively connected with the second end of the first resistor and the collector electrode of the first triode, the base electrode of the first triode is connected with the first end of the fourth resistor, the second end of the fourth resistor is respectively connected with the second end of the second resistor and the base electrode of the second triode, and the collector electrode of the second triode is connected with the second end of the third resistor; an emitting electrode of the second triode is connected with a first end of a sixth resistor, a second end of the sixth resistor is respectively connected with a negative input end of a power supply of the narrow pulse width square wave circuit and a first end of a seventh resistor, a second end of the seventh resistor is connected with a first end of a fifth resistor, and a second end of the fifth resistor is connected with an emitting electrode of the first triode; the second end of the seventh resistor is the output end of the overcurrent detection circuit.
In a second aspect, an electronic device includes the temperature drift resistant overcurrent detection circuit of the first aspect.
The utility model provides a pair of anti temperature drift's overcurrent detection circuit and electronic equipment, the component that uses simply realizes overcurrent detection and prevents the overloaded function of circuit, has improved anti temperature drift characteristic, has simplified circuit structure, the cost is reduced, has improved the reliability.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.
Fig. 1 is a schematic circuit diagram of an embodiment of the present invention.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.
It is to be noted that unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the present invention belongs.
As shown in fig. 1, an embodiment of the present invention provides an anti-temperature drift overcurrent detection circuit, which includes an R1 resistor, an R2 resistor, an R3 resistor, an R4 resistor, an R5 resistor, an R6 resistor, an R7 resistor, a VT1 triode, a VT2 triode, a narrow pulse width square wave circuit N1, and a field effect transistor VM 1. The narrow pulse width square wave circuit N1 has the functions of detecting external voltage and determining the self working mode according to the external voltage, and when the voltage of a trigger terminal, namely the external voltage is higher than a certain value, the narrow pulse width square wave circuit N1 outputs high level; when the trigger voltage is lower than a certain value, the narrow pulse width square wave circuit N1 periodically outputs a square wave signal with a small duty ratio.
P1, P2, P3 and P4 are external interfaces of the overcurrent detection circuit, P1 and P2 are in the same high-voltage network, P4 is an input end of the overcurrent detection circuit, and P3 is an output end of the overcurrent detection circuit. The high-voltage network is connected with a power supply positive port of an R1 resistor, an R2 resistor, an R3 resistor and an N1 narrow pulse width square wave circuit, the other end of the R1 resistor is respectively connected with a collector of a VT1 triode and an external voltage detection port, namely a trigger end, of the N1 narrow pulse width square wave circuit, a base of the VT1 triode is connected with one end of the R4 resistor, an emitter of the VT1 triode is connected with one end of the R5 resistor, the other end of the R5 resistor is respectively connected with a P3 port and one end of the R7 resistor, the other end of the R7 resistor is respectively connected with a power supply negative port of the N1 narrow pulse width square wave circuit and a source of a VM1 field effect transistor, a drain of the VM1 field effect transistor is connected with a P4 port, and a grid of the VM1 field effect transistor is connected with an output port of the N1 narrow pulse width square wave circuit; the other end of the R2 resistor is respectively connected with the other end of the R4 resistor and the base electrode of the VT2 triode, the other end of the R3 resistor is connected with the collector electrode of the VT2 triode, and the emitter electrode of the VT2 triode is connected with the other end of the R6 resistor.
When current flows through the R7 resistor, the R7 resistor generates voltage drop and is superposed on the R6 resistor and the emitter junction of the VT2 triode, the base electrode potential of the VT1 triode is increased, the emitter junction current is increased, and a tiny signal generated by the R7 resistor is amplified; when the current flowing through the R7 resistor is relatively low and is not enough to drive the potential of the collector of the VT1 triode to drop to a certain value, the N1 narrow pulse width square wave circuit can continuously output high level to drive the VM1 field effect tube to be continuously conducted, so that the circuit works normally; when the current flowing through the R7 resistor is increased to reduce the collector potential of the VT1 triode to a certain value, the N1 narrow pulse width square wave circuit is triggered to work, the periodical on-off of the VM1 field effect transistor is controlled, the on-time of the VM1 field effect transistor is far shorter than the off-time, and whether the current of the circuit exceeds the limit or not is repeatedly detected so as to achieve the purpose of overcurrent detection. Wherein the VT2 triode is used for directly setting the static operating point of the VT 1. The model of the VT2 triode is the same as that of the VT1 triode, and when the environmental temperature changes, the emitter junction voltage drops of the VT1 triode and the VT2 triode change together, and the change rates are the same. The static working point of the VT1 triode is automatically adjusted by the VT2 triode of the same model, thereby realizing the function of temperature drift resistance and relatively improving the precision of micro voltage measurement.
In this embodiment, the R4, R5, and R6 resistors function to fine tune the quiescent operating point, and the R2 resistor provides bias voltage for the VT1 transistor. N1 is a narrow pulse width square wave circuit controlled by VT1 transistor collector.
Based on the same inventive concept, the present embodiment also provides an electronic device including the above-mentioned temperature drift resistant overcurrent detection circuit.
The embodiment of the utility model provides a pair of anti temperature drift's overcurrent detection circuit and electronic equipment uses simple and reliable component to realize overcurrent detection and prevent circuit overload's function, has improved anti temperature drift characteristic, has simplified circuit structure, the cost is reduced, has improved the reliability.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the scope of the embodiments of the present invention, and are intended to be covered by the claims and the specification.
Claims (2)
1. A temperature drift resistant overcurrent detection circuit, characterized by: the circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a first triode, a second triode, a narrow pulse width square wave circuit and a field effect tube; the drain electrode of the field effect tube is the input end of the overcurrent detection circuit, the grid electrode of the field effect tube is connected with the output end of the narrow pulse width square wave circuit, and the source electrode of the field effect tube is connected with the negative input end of the power supply of the narrow pulse width square wave circuit; the power supply positive input end of the narrow pulse width square wave circuit, the first end of the first resistor, the first end of the second resistor and the first end of the third resistor are connected with a high-voltage power supply; the trigger end of the narrow pulse width square wave circuit is respectively connected with the second end of the first resistor and the collector electrode of the first triode, the base electrode of the first triode is connected with the first end of the fourth resistor, the second end of the fourth resistor is respectively connected with the second end of the second resistor and the base electrode of the second triode, and the collector electrode of the second triode is connected with the second end of the third resistor; an emitting electrode of the second triode is connected with a first end of a sixth resistor, a second end of the sixth resistor is respectively connected with a negative input end of a power supply of the narrow pulse width square wave circuit and a first end of a seventh resistor, a second end of the seventh resistor is connected with a first end of a fifth resistor, and a second end of the fifth resistor is connected with an emitting electrode of the first triode; the second end of the seventh resistor is the output end of the overcurrent detection circuit.
2. An electronic device, characterized in that: comprising an overcurrent detection circuit as claimed in claim 1, which is resistant to temperature drift.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202023169593.4U CN214067261U (en) | 2020-12-24 | 2020-12-24 | Temperature drift resistant overcurrent detection circuit and electronic equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202023169593.4U CN214067261U (en) | 2020-12-24 | 2020-12-24 | Temperature drift resistant overcurrent detection circuit and electronic equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN214067261U true CN214067261U (en) | 2021-08-27 |
Family
ID=77387307
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202023169593.4U Active CN214067261U (en) | 2020-12-24 | 2020-12-24 | Temperature drift resistant overcurrent detection circuit and electronic equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN214067261U (en) |
-
2020
- 2020-12-24 CN CN202023169593.4U patent/CN214067261U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5088334B2 (en) | Optical receiver circuit | |
| CN110275566A (en) | Voltage regulator | |
| CN213423793U (en) | Linear constant current source and laser | |
| CN213398704U (en) | Current detection circuit | |
| CN113219233B (en) | Voltage expansion circuit for high-side current sampling | |
| CN214067261U (en) | Temperature drift resistant overcurrent detection circuit and electronic equipment | |
| CN104882856A (en) | High-precision over-current detection circuit | |
| CN103743934A (en) | High-precision high-side current detection circuit | |
| CN103941794A (en) | Series connection type transistor voltage stabilizing circuit with differential amplification function | |
| CN112558679A (en) | Current-limiting protection circuit | |
| CN203178843U (en) | Temperature compensation system | |
| CN112485494A (en) | Current detection circuit based on triode | |
| KR100426150B1 (en) | Power supply for individually controlling discharge current and absorbing current as output current supplied to load | |
| CN109474246B (en) | Voltage clamping protection structure and operational amplifier input stage structure | |
| US8648641B2 (en) | Voltage controlled variable resistor suitable for large scale signal application | |
| CN109254188B (en) | High-speed current detection circuit suitable for switching power supply | |
| CN205193056U (en) | Water quality testing circuit based on three -terminal voltage regulator tube steady voltage design | |
| CN212808411U (en) | High-sensitivity current detection circuit | |
| CN205450857U (en) | No branch road leakage current's active current limit circuit | |
| CN218383029U (en) | Low-cost over-current detection and current detection circuit | |
| CN210669886U (en) | Current and voltage superposition type quick discharge circuit | |
| CN216599005U (en) | Reverse connection prevention circuit | |
| CN218679009U (en) | High-precision thermocouple interface amplifying circuit and electrical equipment thereof | |
| CN105158430A (en) | Water quality testing circuit based on three-terminal voltage-regulator tube voltage regulation design | |
| CN211209292U (en) | Overcurrent and overvoltage protection circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |