Circuit capable of improving surge voltage resistance of power supply end of ignition module

Abstract

The utility model discloses a circuit capable of improving surge voltage resistance of a power supply end of an ignition module, which comprises a voltage stabilization module and a protection module connected to a power supply input end of the voltage stabilization module. The protection module comprises an anti-surge protection unit used for resisting surge voltage interference, an instant voltage suppression unit used for suppressing instant overvoltage, and a negative voltage protection unit used for protecting the voltage stabilization module from negative voltage interference. One end of the anti-surge protection unit is connected with a vehicle-mounted power supply, and the other end of the anti-surge protection unit is connected with the instantaneous voltage suppression unit and the negative voltage protection unit. According to the utility model, different voltage interferences generated under various vehicle conditions are considered, and the protection module is additionally arranged at the power supply input end of the voltage stabilization module, so that the power supply port of the ignition module can bear higher surge voltage interferences and is not damaged, and the ignition module can still work normally under severe vehicle conditions and has strong anti-interference performance.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile ignition modules, in particular to a circuit capable of improving the surge voltage resistance capability of a power supply terminal of an ignition module. Background Art

[0002] There are some ignition modules with complex functions in the automotive market. The functions of these ignition modules are realized through integrated chip programming control. There are two types of automotive electronic control systems: 12V system and 24V system. The power supply voltage is 12V and 24V respectively. The power supply voltage of mainstream integrated chips is usually 5V. Therefore, it is necessary to design a step-down circuit at the power supply end of the ignition module to provide a suitable power supply voltage for the integrated chip. At present, the step-down is mainly achieved through the LDO voltage regulator circuit, such as Figure 1 At the same time, various complex driving conditions may occur during the driving process of the car. Different driving conditions will cause certain disturbances to the voltage of the car's electronic control system, generate surge voltage on the power line, and the power supply end of the ignition module will be disturbed by the surge voltage.

[0003] However, the existing ignition module design lacks consideration for the complex vehicle conditions. Most of the existing ignition modules on the market do not meet the requirements of the ISO-7637 transient conduction immunity test standard, and do not provide sufficient protection for the LDO itself in the LDO voltage regulator circuit. In actual automotive operation, when the power supply end of the ignition module is disturbed by a relatively large surge voltage, the LDO in the LDO voltage regulator circuit at the power supply end may be damaged by the surge voltage, and the LDO voltage regulator circuit fails and cannot provide a stable voltage to the subsequent circuit, and may even damage the subsequent circuit and integrated chip, causing the ignition module to malfunction or short-circuit, and in severe cases, it may cause the ignition coil to burn, and ultimately cause the vehicle engine to be abnormal and unable to drive normally. Utility Model Content

[0004] The purpose of the utility model is to provide a circuit that can improve the surge voltage resistance of the power supply terminal of the ignition module. Taking into account the different voltage interferences generated under various vehicle conditions of the car, a protection module is added to the power input end of the voltage stabilizing module, so that the power supply port of the ignition module can withstand higher surge voltage interference without being damaged. The ignition module can still maintain normal operation under harsh vehicle conditions and has strong anti-interference performance.

[0005] In order to achieve the above purpose, the following technical solutions are adopted:

[0006] A circuit capable of improving the surge voltage resistance capability of an ignition module power supply terminal comprises a voltage stabilizing module and a protection module connected to the power supply input terminal of the voltage stabilizing module; the protection module comprises an anti-surge protection unit for resisting surge voltage interference, a transient voltage suppression unit for suppressing transient overvoltage, and a negative voltage protection unit for protecting the voltage stabilizing module from negative voltage interference; one end of the anti-surge protection unit is connected to a vehicle-mounted power supply, and the other end is respectively connected to the transient voltage suppression unit and the negative voltage protection unit.

[0007] Preferably, the voltage stabilizing module includes a transistor Q1 and a series voltage stabilizing unit for providing a stable voltage to the base of the transistor Q1; the emitter of the transistor Q1 is used to output a stable voltage to a subsequent circuit.

[0008] Preferably, the anti-surge protection unit comprises a resistor R1 and a resistor R2 connected in parallel; a first end of the resistor R1 and the resistor R2 connected in parallel is connected to the positive electrode of the vehicle power supply.

[0009] Preferably, the transient voltage suppression unit comprises a transient voltage suppression diode D1; one end of the transient voltage suppression diode D1 is connected to the anti-surge protection unit, and the other end is grounded.

[0010] Preferably, the negative voltage protection unit includes a switching diode D2; the anode of the switching diode D2 is connected to the anti-surge protection unit, and the cathode of the switching diode D2 is connected to the collector of the transistor Q1.

[0011] Preferably, the protection module further includes a filter capacitor C1 connected in parallel with the transient suppression diode D1.

[0012] Preferably, the series voltage stabilization unit includes a resistor R3 and a diode D3; the first end of the resistor R3 is connected to the positive electrode of the switching diode D2, and the second end of the resistor R3 is connected to the base of the transistor Q1; the cathode of the diode D3 is connected to the base of the transistor Q1, and the anode of the diode D3 is grounded.

[0013] Preferably, it also includes a capacitor C2 and a capacitor C3 connected in parallel for filtering out high-frequency and low-frequency interference; the capacitor C2 and the capacitor C3 are both connected to the emitter of the transistor Q1 at one end and grounded at the other end.

[0014] Preferably, a resistor R4 connected to the emitter of the transistor Q1 is further included to protect the voltage output port from surge interference.

[0015] By adopting the above scheme, the beneficial effects of the utility model are:

[0016] The utility model provides a circuit that can improve the surge voltage resistance of the power supply end of the ignition module. Taking into account the different voltage interferences generated under various vehicle conditions, a protection module is added to the power input end of the voltage regulator module, so that the power supply port of the ignition module can withstand higher surge voltage interference without being damaged. The ignition module can still maintain normal operation under harsh vehicle conditions and has strong anti-interference. In the preferred solution, a newly designed voltage regulator module is used at the power supply end of the ignition module to replace the traditional LDO voltage regulator circuit to power the integrated chip control circuit of the subsequent stage, thereby reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the existing LDO voltage stabilization circuit diagram;

[0018] Figure 2 A circuit diagram of the utility model;

[0019] The accompanying drawings illustrate:

[0020] 1—voltage stabilizing module, 2—protection module. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0022] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0023] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0024] Reference Figure 2The utility model provides a circuit that can improve the surge voltage resistance capability of the power supply end of an ignition module, comprising a voltage stabilizing module 1, and a protection module 2 connected to the power input end of the voltage stabilizing module 1; the protection module 2 comprises an anti-surge protection unit for resisting surge voltage interference, a transient voltage suppression unit for suppressing transient overvoltage, and a negative voltage protection unit for protecting the voltage stabilizing module 1 from negative voltage interference; one end of the anti-surge protection unit is connected to the vehicle-mounted power supply, and the other end is respectively connected to the transient voltage suppression unit and the negative voltage protection unit.

[0025] The utility model takes into account the different voltage interferences generated under various vehicle conditions, and adds a protection module 2 to the power input end of the voltage stabilizing module 1, so that the power port of the ignition module can withstand higher surge voltage interference without being damaged. The ignition module can still maintain normal operation under harsh vehicle conditions and has strong anti-interference performance. Determine the circuit logic, including:

[0026] 1) The voltage stabilizing module 1 used can provide a stable voltage drive to the subsequent circuit, and the voltage must be large enough to ensure the normal operation of the integrated chip;

[0027] 2) A protection module 2 is added to the power input end of the voltage stabilizing module 1 . The protection module 2 should be able to effectively protect the voltage stabilizing module 1 from being damaged by surge voltage and should not affect the normal function of the voltage stabilizing module 1 .

[0028] Please continue to refer to Figure 2 , B+ is connected to the positive pole of the vehicle power supply, GND is connected to the ground, and Vcc is the voltage output port to power the integrated chip and other subsequent circuits.

[0029] The voltage stabilizing module 1 includes a transistor Q1 and a series voltage stabilizing unit for providing a stable voltage to the base of the transistor Q1; the emitter of the transistor Q1 is used to output a stable voltage to a subsequent circuit.

[0030] The anti-surge protection unit includes a resistor R1 and a resistor R2 connected in parallel; the first end of the resistor R1 and the resistor R2 connected in parallel is connected to the positive electrode of the vehicle power supply. The resistor R1 and the resistor R2 in the anti-surge protection unit are two parallel anti-surge resistors. The parallel connection can improve the voltage surge protection capability while reducing the influence of the voltage division on the resistor on the subsequent driving capability.

[0031] The transient voltage suppression unit includes a transient voltage suppression diode D1; one end of the transient voltage suppression diode D1 is connected to the anti-surge protection unit, and the other end is grounded. The transient voltage suppression diode D1 (TVS) is used to suppress transient overvoltage and protect various components in the subsequent circuit from being damaged by transient surge pulse voltage.

[0032] The negative voltage protection unit includes a switching diode D2; the positive electrode of the switching diode D2 is connected to the anti-surge protection unit, and the negative electrode of the switching diode D2 is connected to the collector of the transistor Q1. The switching diode D2 plays a negative voltage protection role, protecting the transistor Q1 from being damaged by negative voltage interference.

[0033] The protection module 2 further includes a filter capacitor C1 connected in parallel with the transient suppression diode D1.

[0034] The series voltage stabilizing unit includes a resistor R3 and a diode D3; the first end of the resistor R3 is connected to the positive electrode of the switch diode D2, and the second end of the resistor R3 is connected to the base of the transistor Q1; the cathode of the diode D3 is connected to the base of the transistor Q1, and the positive electrode of the diode D3 is grounded. The resistor R3 and the diode D3 form a series voltage stabilizing unit, which provides a stable voltage to the base of the transistor Q1; the transistor Q1 is an NPN transistor, which works in the saturation region, and the emitter of the transistor Q1 outputs a stable voltage to each circuit of the subsequent stage.

[0035] Furthermore, the utility model provides a circuit that can improve the surge voltage resistance of the power supply end of the ignition module, and also includes a capacitor C2 and a capacitor C3 connected in parallel, and the capacitor C2 and the capacitor C3 are both connected to the emitter of the transistor Q1 at one end and grounded at the other end. The capacitor C2 and the capacitor C3 are two filter capacitors, the capacitor C2 has a large capacitance, and the capacitor C3 has a small capacitance. The combination can filter out high-frequency and low-frequency interference.

[0036] Furthermore, the utility model provides a circuit that can improve the surge voltage resistance of the power supply end of the ignition module, and also includes a resistor R4 connected to the emitter of the transistor Q1. The resistor R4 is an anti-surge resistor and plays a role in protecting the voltage output port.

[0037] The utility model provides a circuit that can improve the surge voltage resistance of the power supply end of the ignition module, so that the surge voltage interference that the ignition module can withstand even exceeds the requirements of the ISO-7637 transient conduction immunity test standard. When the car is driving, there may be various complex vehicle conditions, and the different voltage interferences generated are applied to the vehicle power supply or the power transmission line. When the interference is transmitted to the power supply port of the ignition module, the surge voltage will not damage the components of the ignition module and cause failure, but will be gradually attenuated and weakened by the resistor R1, the resistor R2, the transient suppression diode D1, the filter capacitor C1, the switch diode D2, the transistor Q1, etc. Absorbed, so that the ignition module can still maintain normal operation under harsh vehicle conditions.

[0038] The above are only preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included in the protection scope of the present utility model. Obviously, the above embodiments of the present utility model are only examples for clearly illustrating the present utility model, and are not limitations on the implementation methods of the present utility model. For ordinary technicians in the relevant field, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present utility model. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included in the protection scope of the claims of the present utility model.

Claims

1. A circuit capable of improving the surge voltage resistance capability of the power supply terminal of an ignition module, characterized in that: It includes a voltage stabilizing module and a protection module connected to the power input end of the voltage stabilizing module; the protection module includes an anti-surge protection unit for resisting surge voltage interference, a transient voltage suppression unit for suppressing transient overvoltage, and a negative voltage protection unit for protecting the voltage stabilizing module from negative voltage interference; one end of the anti-surge protection unit is connected to the vehicle power supply, and the other end is respectively connected to the transient voltage suppression unit and the negative voltage protection unit.

2. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 1, characterized in that: The voltage stabilizing module includes a transistor Q1 and a series voltage stabilizing unit for providing a stable voltage to the base of the transistor Q1; the emitter of the transistor Q1 is used to output a stable voltage to a subsequent circuit.

3. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 1, characterized in that: The anti-surge protection unit includes a resistor R1 and a resistor R2 connected in parallel; a first end of the resistor R1 and the resistor R2 connected in parallel is connected to the positive electrode of the vehicle power supply.

4. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 1, characterized in that: The transient voltage suppression unit includes a transient voltage suppression diode D1; one end of the transient voltage suppression diode D1 is connected to the anti-surge protection unit, and the other end is grounded.

5. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 2, characterized in that: The negative voltage protection unit includes a switching diode D2; the anode of the switching diode D2 is connected to the anti-surge protection unit, and the cathode of the switching diode D2 is connected to the collector of the transistor Q1.

6. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 4, characterized in that: The protection module further includes a filter capacitor C1 connected in parallel with the transient suppression diode D1.

7. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 5, characterized in that: The series voltage stabilizing unit includes a resistor R3 and a diode D3; the first end of the resistor R3 is connected to the positive electrode of the switching diode D2, and the second end of the resistor R3 is connected to the base of the transistor Q1; the cathode of the diode D3 is connected to the base of the transistor Q1, and the anode of the diode D3 is grounded.

8. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 2, characterized in that: It also includes a capacitor C2 and a capacitor C3 connected in parallel, which are used to filter out high-frequency and low-frequency interference; one end of the capacitor C2 and the capacitor C3 are connected to the emitter of the transistor Q1, and the other end is grounded.

9. The circuit for improving the surge voltage resistance capability of the power supply terminal of the ignition module according to claim 2, characterized in that: The device also includes a resistor R4 connected to the emitter of the transistor Q1 for protecting the voltage output port from surge interference.

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