Digital Fuel Gauge

Description: This circuit utilizes a digital voltmeter, constructed from IC1 and IC3, to indicate fuel quantity as a percentage of a full tank. It is designed to accommodate two types of fuel sensors, where low resistance corresponds to a full tank and higher resistance indicates an empty tank. IC2 serves as a DC amplifier, featuring both inverting (path A) and non-inverting (path B) outputs, along with calibration adjustments for each path.

The circuit operates by interpreting the resistance values from the fuel sensors, which vary based on the fuel level. In the case of a low-resistance sensor, the output from the sensor is directly proportional to the fuel level, while a high-resistance sensor operates inversely. This dual compatibility is crucial for applications where different sensor types may be used.

IC2, the DC amplifier, is configured to amplify the voltage signal derived from the fuel sensors. The inverting output (path A) and non-inverting output (path B) allow for flexibility in signal processing. Calibration adjustments are essential for ensuring accurate readings across different sensor types. These adjustments can be made using variable resistors connected to the amplifier, enabling precise tuning of the output signal to match the characteristics of the selected sensor type.

The digital voltmeter, composed of IC1 and IC3, interprets the amplified voltage signal and converts it to a percentage display. This display provides a clear and immediate indication of the fuel level, facilitating monitoring and management of fuel resources. Overall, the circuit is designed for reliability and accuracy, making it suitable for a variety of automotive and industrial applications where fuel level monitoring is critical. This circuit uses a digital voltmeter (formed from IC1 and IC3) to display fuel quantity as a percentage of a full tank. In order to work with two lands of fuel sensors, low resistance = full. Where higher resistance = full, IC2 forms a dc amplifier that has both inverting (path A) or noninverting (path B) outputs, and calibration adjustments for each path.