The gas tank on your car has a fuel-level sending unit that works like a potentiometer. A float moves up and down while the gasoline level, changing the variable resistor setting and producing a voltage proportional to the gas level. A full tank produces 12V, and an empty tank produces 0V. Design a Multisim circuit using an LM339 that turns on "Fuel Level" indicator lamp when the voltage level from the sending unit gets below 0.5V.© BrainMass Inc. brainmass.com March 21, 2019, 7:59 pm ad1c9bdddf
Please see attached files for the circuit of the fuel-level detector. The circuit explanation is also included so that you can understand the circuit schematic better.
Below is the circuit of the simple voltage comparator circuit:
Explanation: The main component used is the LM339 IC, which functions as a comparator. V_SOURCE represents the source signal voltage from the fuel level unit. As stated, V_SOURCE can be from 0V (empty) to 12V (full tank). It is connected to the inverting terminal of the comparator. The non-inverting terminal of the comparator is connected to a simple voltage ...
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