Resistor type analogue signal processing circuit of vehicle-mounted external sensor

Abstract

The invention discloses a resistor type analogue signal processing circuit of a vehicle-mounted external sensor. The resistor type analogue signal processing circuit comprises a catching diode and a reverse connection protection diode which are connected in series between a power source and the ground, the negative electrode of the catching diode is connected with the power source, and the positive electrode of the reverse connection protection diode is grounded; one end of a voltage follower circuit is connected between the positive electrode of the catching diode and the negative electrode of the reverse connection protection diode, the other end of the voltage follower circuit is connected with a resistor type signal end through a first resistor, the first resistor is grounded through a first capacitor and outputs analog voltage through a resistor, and a second resistor is grounded through a second capacitor; the voltage follower circuit can provide a current path for power source short circuit, grounded short circuit and power source reverse connection, protect circuit signal processing safety, improve accuracy of an output power source and reduce conversion errors of analog quantity. The resistor type analogue signal processing circuit of the vehicle-mounted external sensor with existing automobile-level resistors is adopted, so that it is avoided that the resistors are burned because a pull-up resistor is overhigh in power when short circuit appears on a vehicle-mounted storage battery.

Description

technical field [0001] The invention relates to the field of automotive electronics, in particular to a resistance-type analog signal processing circuit for a vehicle-mounted external sensor. Background technique [0002] The currently used on-board external sensors mainly include the following types: intake air pressure temperature sensor, water temperature sensor, oxygen sensor, throttle position sensor, air flow sensor, etc. Intake air pressure and temperature sensor: installed on the intake manifold to provide engine load information and intake air temperature information; water temperature sensor: used in the electronic controller fuel injection device to monitor the temperature of engine cooling water, output voltage signal to the electronic controller As the load information of the engine, so as to make judgments on the working conditions of the engine; oxygen sensor: used in the feedback system of the electronic control device, realizes closed-loop control, and impro...

AI Technical Summary

Problems solved by technology

There are no automotive grade resistors available that meet this need

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