CN217135159U

CN217135159U - Power supply reverse connection protection circuit and device for throttle circuit

Info

Publication number: CN217135159U
Application number: CN202123397378.4U
Authority: CN
Inventors: 李厚望; 陆鑫; 陶磊; 夏鸿飞
Original assignee: Nanjing Aolian Ae & Ea Co ltd
Current assignee: Nanjing Aolian Ae & Ea Co ltd
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2022-08-05
Anticipated expiration: 2031-12-31

Abstract

The utility model discloses a power reversal protection circuit for throttle circuit, including the bleeder unit, prevent the reversal unit, first ground point and second ground point, the bleeder unit includes first resistance and second resistance, prevent the reversal unit and include MOS pipe and first electric capacity, the MOS pipe is equipped with parasitic diode, first resistance first end is connected with throttle circuit power end, first resistance second end is connected with MOS pipe source electrode after establishing ties the second resistance, the node of first resistance and second resistance is connected with the grid of MOS pipe, first resistance first end and MOS pipe drain electrode are connected with throttle circuit power supply, first electric capacity connects in parallel between MOS pipe source electrode and drain electrode, first electric capacity both ends are connected with first ground point and second ground point respectively, first ground connection earth point is connected with the oil gate circuit earthing terminal; the utility model discloses can realize having the low-loss advantage to throttle circuit power transposition protection, can stabilize the power supply to throttle circuit, can not influence throttle circuit output signal, be applicable to throttle circuit power transposition protection.

Description

Power supply reverse connection protection circuit and device for throttle circuit

Technical Field

The utility model belongs to the technical field of automotive electronics, concretely relates to power transposition protection circuit and device for throttle circuit.

Background

With the improvement of living standard, the popularity of automobiles as vehicles is higher and higher. In order to improve the safety of automobiles, higher requirements are placed on the reliability of automobile electronic circuits. The electronic throttle of the automobile is an important safety component of the whole automobile, and the throttle circuit arranged in the electronic throttle is also important correspondingly. In order to ensure the safety of the accelerator circuit, the stable operation of internal elements of the circuit is ensured, and the stability of a power supply of the accelerator circuit is also ensured, for example, if the power supply of the accelerator circuit has a reverse polarity fault, the accelerator circuit is greatly damaged, so that an electronic accelerator of an automobile fails, thereby not only damaging core components of the automobile, but also causing accidents to the running automobile. Traditional electronic throttle does not possess the function of power reversal protection, and the wide use diode realizes the protection of power reversal among the prior art, but the great meeting of consumption of diode produces certain pressure drop, is unfavorable for the stable power supply to throttle circuit, especially can exert an influence to throttle circuit's output signal, can not be applicable to throttle circuit's power reversal protection.

Disclosure of Invention

The utility model aims to solve the technical problem of the power reversal protection of throttle circuit, the utility model provides a power reversal protection circuit and device for throttle circuit not only can realize the power reversal protection to the throttle circuit, still has low-loss advantage, can stabilize the power supply to the throttle circuit, can not influence the output signal of throttle circuit, is applicable to the power reversal protection of throttle circuit.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a power supply reverse connection protection circuit for an accelerator circuit comprises a voltage division unit, a reverse connection prevention unit, a first grounding point and a second grounding point; the voltage division unit comprises a first resistor and a second resistor, the reverse connection prevention unit comprises an MOS (metal oxide semiconductor) tube and a first capacitor, the MOS tube is an N-channel enhanced MOS tube provided with a parasitic diode, and the anode and the cathode of the parasitic diode are respectively connected with the source electrode and the drain electrode of the MOS tube; the first end of the first resistor and the drain electrode of the MOS tube are respectively used as a first power supply input end and a second power supply input end of the power supply reverse connection protection circuit, and the first end of the first resistor and the drain electrode of the MOS tube are connected with a power supply source of the accelerator circuit; the first capacitor is connected between the source electrode and the drain electrode of the MOS tube in parallel, two ends of the first capacitor are respectively connected with the first grounding point and the second grounding point, and the first grounding point is connected with the grounding end of the oil gate circuit.

The utility model discloses the first end of well first resistance and the drain electrode of MOS pipe are as first power input end and second power input end, are connected with throttle circuit power supply respectively, and are specific: 1) (ii) a When the first power supply input end and the second power supply input end are respectively connected with the cathode and the anode of a power supply, in order to generate a power supply reverse connection condition, the parasitic diode cannot be conducted, the potential difference between the base electrode and the source electrode of the MOS tube is zero, a conductive channel cannot be formed between the drain electrode and the source electrode, and the MOS tube is in a cut-off state, so that a loop cannot be formed between the power supply and the accelerator circuit, and the power supply reverse connection protection of the accelerator circuit is realized; 2) when the first power supply input end and the second power supply input end are respectively connected with the anode and the cathode of a power supply, a parasitic diode is conducted under the condition that the power supply is normally connected, the potential difference between the base electrode and the source electrode of an MOS (metal oxide semiconductor) tube is greater than the starting voltage of the MOS tube, a conductive channel is formed between the drain electrode and the source electrode, the forward voltage is applied to the MOS tube from the drain electrode to the source electrode, and the MOS tube is in a conducting state, so that a loop is formed between the power supply and an accelerator circuit; under the condition that the MOS pipe switched on, the internal resistance between source electrode and the drain electrode is minimum for parasitic diode short circuit, the pressure drop is nearly zero, thereby the utility model has the advantages of low-loss can all stabilize the power supply to throttle circuit, can not influence throttle circuit's output signal. The utility model discloses well first resistance and second resistance constitute bleeder circuit, carry out the partial pressure to the voltage that power supply got into, and the potential difference between base and the source electrode equals the partial pressure on the second resistance in the MOS pipe, when concrete implementation, can set up the resistance of first resistance and second resistance as required. In the utility model, when the automobile is not ignited to be started, the power supply does not work, the MOS tube is in a cut-off state, when the automobile is ignited to be started, the power supply starts to work, if a reverse connection fault occurs, the MOS tube is kept in a cut-off state for the occurrence of a power reverse connection condition, and if the power supply is normally connected, the MOS tube is changed from a cut-off state to a conduction state; the MOS tube is switched from cut-off to conduction or from conduction to cut-off, namely the switch of the MOS tube is switched on and off, and the switch of the MOS tube is too rapid and can generate spike pulse, therefore, the utility model has the advantages that the first capacitor is connected in parallel between the source electrode and the drain electrode of the MOS tube, and the generation of the spike pulse can be prevented; however, the utility model discloses in normally insert the circumstances that power reversal or power reversal connect to normal access along with power supply, the switching can take place for the power polarity at first electric capacity both ends, in the twinkling of an eye that power polarity was switched, voltage on the first electric capacity can discharge through power supply or throttle circuit, leads to the damage of electric capacity, power supply and throttle circuit easily, from this, the utility model discloses in set up first ground point and second ground point, in the twinkling of an eye that power polarity was switched, can introduce ground with the electricity discharge of first electric capacity.

It is right to the utility model discloses technical scheme's further injects, still includes the plug connector, and the first end of first resistance and the drain electrode of MOS pipe pass through the plug connector and are connected with throttle circuit's power supply. The utility model discloses in set up the plug connector and be used for external power supply, the operation of being convenient for.

It is right to the utility model discloses technical scheme's further injecture, the plug connector is connected with throttle circuit's signal output part for pass through the plug connector output with throttle circuit's signal. The utility model discloses the circuit is used with the cooperation of throttle circuit, when concrete implementation, passes through plug connector output with the signal of throttle circuit, simple structure, the operation of being convenient for.

A power supply reverse connection protection device for an accelerator circuit comprises a circuit board and the power supply reverse connection protection circuit, wherein the power supply reverse connection protection circuit is arranged on the circuit board. The utility model discloses with the power reverse connection circuit set up when on the circuit board adopt among the prior art conventional means can, will the power reverse connection protection circuit sets up the forming device on the circuit board, convenient installation when concrete implementation.

Compared with the prior art, the utility model discloses beneficial effect is: the utility model discloses not only can realize still having the advantage of low loss to the power reversal protection of throttle circuit, can stabilize the power supply to throttle circuit, can not influence the output signal of throttle circuit, be applicable to the power reversal protection of throttle circuit.

Drawings

Fig. 1 is a circuit diagram of embodiment 1 of the present invention.

Fig. 2 is a circuit diagram of embodiment 2 of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the drawings and specific embodiments.

Example 1

As shown in fig. 1, a power reverse connection protection circuit for an accelerator circuit includes a voltage dividing unit, a reverse connection prevention unit, a first ground point and a second ground point; the voltage dividing unit comprises a first resistor R1 and a second resistor R2, the reverse connection preventing unit comprises a MOS tube Q1 and a first capacitor C1, the MOS tube Q1 is an N-channel enhanced MOS tube provided with a parasitic diode D1, and the anode and the cathode of the parasitic diode D1 are respectively connected with the source and the drain of the MOS tube Q1; the first end of the first resistor R1 is connected with a power supply end VCC of the accelerator circuit, the second end of the first resistor R1 is connected with a source electrode of the MOS transistor Q1 after being connected with the second resistor R2 in series, nodes of the first resistor R1 and the second resistor R2 are connected with a grid electrode of the MOS transistor Q1, the first end of the first resistor R1 and a drain electrode of the MOS transistor Q1 are respectively used as a first power supply input end A and a second power supply input end B of the power supply reverse connection protection circuit, and the first end of the first resistor R1 and the drain electrode of the MOS transistor Q1 are connected with a power supply of the accelerator circuit; the first capacitor C1 is connected in parallel between the source and the drain of the MOS transistor Q1, two ends of the first capacitor C1 are connected to the first ground point GND1 and the second ground point GND2, respectively, and the first ground point GND1 is connected to the ground point GND of the accelerator circuit.

In this embodiment, the resistances of the first resistor R1 and the second resistor R2 are 27K and 100K, respectively, the first capacitor C1 is a polypropylene capacitor, the capacity of the first capacitor C1 is 100nF, the model of the MOS transistor Q1 is 2N7002/DMG301NU, and the turn-on voltage of the MOS transistor Q1 is 2.1V; the throttle circuit power supply V0 adopts the conventional voltage of the automobile electronic system power supply in the prior art, and is 5V.

In the use of the embodiment, 1) when the first power input end a and the second power input end B are respectively connected to the negative electrode and the positive electrode of the power supply VO, in order to generate a power reverse connection condition, the parasitic diode D1 is not turned on, the potential difference between the base and the source of the MOS transistor Q1 is zero, a conductive channel cannot be formed between the drain and the source, and the MOS transistor Q1 is in a cut-off state, so that a loop cannot be formed between the power supply V0 and the accelerator circuit, thereby realizing power reverse connection protection of the accelerator circuit;

2) when the first power input end a and the second power input end B are respectively connected to the anode and the cathode of the power supply VO, for the normal connection condition of the power supply V0, the parasitic diode D1 is turned on, and the potential difference between the base and the source of the MOS transistor Q1 is the divided voltage on the second resistor R2: VR2= V0 × [ R2/(R1+ R2) ] =5V × [100K/(27K +100K) ] = 3.93V; VR2=3.93V is greater than MOS pipe Q1 turn-on voltage 2.1V, form the conducting channel between drain electrode and the source electrode, the drain electrode is the forward voltage to the source electrode in MOS pipe Q1, MOS pipe Q1 is in the conducting state, make power supply V0 and throttle circuit form the return circuit; meanwhile, when the diode is used for realizing the reverse connection protection of the power supply in the prior art, 0.7V voltage drop is generally generated, and when the MOS transistor Q1 is turned on in the embodiment, the internal resistance between the source electrode and the drain electrode is extremely small, so that the parasitic diode D1 is short-circuited, and the voltage drop is nearly zero.

Example 2

Compared with embodiment 1, the present embodiment further includes a plug JP1, as shown in fig. 2, a first end of the first resistor R1 is connected to pin 1 of plug JP1, a drain of the MOS transistor Q1 is connected to pin 2 of plug JP1, and pin 1 and pin 2 of plug JP1 correspond to the second power input terminal B and the first power input terminal a in embodiment 1; pin 3 of the plug connector JP1 is connected with a signal output end OUT of the throttle circuit and used for outputting signals of the throttle circuit through the plug connector JP 1.

When the power supply is used in the embodiment, when the pin 1 and the pin 2 of the plug JP1 are respectively connected with the positive electrode and the negative electrode of the power supply VO, in order to generate the condition of power reverse connection, when the pin 1 and the pin 2 of the plug JP1 are respectively connected with the negative electrode and the positive electrode of the power supply VO, the power supply V0 is normally connected.

Example 3

A power supply reverse connection protection device for an accelerator circuit comprises a circuit board and the power supply reverse connection protection circuit, wherein the power supply reverse connection protection circuit is arranged on the circuit board. In this embodiment, the power supply reverse connection circuit is disposed on the circuit board by a conventional method in the prior art, which is not an improvement point of this embodiment and is not described herein.

Claims

1. The utility model provides a power reverse connection protection circuit for throttle circuit which characterized in that: the voltage divider comprises a voltage dividing unit, an anti-reverse connection unit, a first grounding point and a second grounding point;

the voltage division unit comprises a first resistor and a second resistor, the reverse connection prevention unit comprises an MOS (metal oxide semiconductor) tube and a first capacitor, the MOS tube is an N-channel enhanced MOS tube provided with a parasitic diode, and the anode and the cathode of the parasitic diode are respectively connected with the source electrode and the drain electrode of the MOS tube;

the first end of the first resistor and the drain electrode of the MOS tube are respectively used as a first power supply input end and a second power supply input end of the power supply reverse connection protection circuit, and the first end of the first resistor and the drain electrode of the MOS tube are connected with a power supply of the accelerator circuit;

the first capacitor is connected between the source electrode and the drain electrode of the MOS tube in parallel, two ends of the first capacitor are respectively connected with the first grounding point and the second grounding point, and the first grounding point is connected with the grounding end of the oil gate circuit.

2. A power supply reverse connection protection circuit for a throttle circuit as claimed in claim 1, wherein: the first end of the first resistor and the drain electrode of the MOS tube are connected with a power supply of the accelerator circuit through the plug connector.

3. A power supply reverse connection protection circuit for a throttle circuit as claimed in claim 2, wherein: the plug connector is connected with the signal output end of the throttle circuit and used for outputting the signal of the throttle circuit through the plug connector.

4. The utility model provides a power reverse connection protection device for throttle circuit which characterized in that: the reverse power protection circuit comprises a circuit board and the reverse power protection circuit as claimed in any one of claims 1 to 3, wherein the reverse power protection circuit is arranged on the circuit board.