Most efficient & cheapest way to create a simple voltage offset

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1

Hello,

New to the forums here. I work in the auto industry and have a little project I thought someone here might be able to help with. I want to take a 0-1 volt analog signal from a sensor and apply a small voltage offset to it, either in the positive or negative direction (i.e., capability for both).

For example, if the sensor output a steady 0.8 volts, and I applied a fixed +0.1 V offset, said device would give me an output voltage of 0.9V. In reality, the voltage from my sensor will always be fluctuating between ~0.1 and 0.9 volts, but the idea is to have the offset apply to this varying input, regardless of where the input value lies within the 0.1-0.9V range at any given time, at least initially.

In the long term, I can see the need to maybe apply a floor or ceiling voltage so that the lower and upper limits of 0.1 and 0.9 are not exceeded (i.e., we don’t go lower than 0.1V or higher than 0.9V on the output).

I can also envision the offset voltage value changing as a function of some other analog voltage input (e.g., from another sensor).

The applied offset will likely stay in the range of +/- 0.3V.

Suggestions?

Thanks!

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If you want to do some initial research, I think you’re describing [biasing.](Biasing - Wikipedia)

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I’m guessing O2 sensor based on the voltage range? Regardless of which sensor, what you should look into is an op amp, configured as a differential amplifier, with unity gain. This will allow you to add / subtract either a fixed of varying offset from the input signal. Since your application is automotive, and you probably want to keep the power supply simple, try to select an op amp that can operate from a single-sided supply.