| 摘要 |
PURPOSE: A three-wire fuel gauge circuit for a vehicle is provided to minimize foreign matters between a variable resistance part and a contact point part, and to indicate the fuel amount accurately by controlling an indicator according to a resistance signal from an output terminal of the contact point part and voltage from resistance of a ground resistor. CONSTITUTION: A circuit of a fuel sender is composed of a voltage terminal(25a) and a ground terminal of a variable resistance part(25), and an output terminal(23a) of a contact point part(23) rotated and contacted to the variable resistance part. Reference voltage is applied to the voltage terminal, and a ground resistor is connected to a branch circuit from a circuit connecting the output terminal of the contact point part and a CPU(central processing unit) of a microcomputer(26). The microcomputer detects the resistance signal from the output terminal of the contact point part and voltage fluctuation from resistance of the ground resistor, and controls the indicator of a fuel gauge(30).
|
