A Cost-Competitive Twin Programmable Microcontroller-based Digital Potentiometer for Low Range Resistance Application in Automotive Testing

Abstract

Fuel Volume and Engine Temperature embedded inside Automotive Instrument Cluster react according to the resistance-based signal received from the fuel tank and temperature sensor. A potentiometer or decade resistance box is connected to the cluster’s pin-out to simulate the reading of the gauges when turning the knob of the potentiometer or the resistance board. This manual testing method is tiresome for repetitive test procedure thus may lead to human error. Available Commercial-Off-The-Shelf simulators with programmable resistor module are costly and most of the time its abundance of functionality is irrelevant with the testing purpose. This proposed cost-competitive twin programmable digital potentiometer uses BCD-method which comprises only 8 sets of relays and resistors on each unit thus capable to generate resistance from 0 Ohm to 255 Ohm.