I am working on a project for work that involves retrofitting a sigma-delta converter onto an existing design. The problem is that the sigma-delta converter has a 0-5V input, but the current circuit has a signal range of -5 to +5.

So I need to add another stage to convert this signal to 0-5V. I figure I could just use a gain of 0.5 for the scaling, but I dont know how to offset it.

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Jeff
To the optimist, the glass is half full.
To the pessimist, the glass is half empty.
To the engineer, the glass is twice as big as it needs to be.

 

hi,
This is a circuit for +/-2.5V input, you could easily modify for +/-5V input.

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Eric
"Good enough is Perfect"

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That circuit inverts the input. This may not be a problem. If it is, you could add another inverter, with appropriate offsetting.
Another way is to use an R-R attenuator (gain=0.5), but instead of returning the other end of the attenuator to GND, return it to a 5.0V reference. You could follow that with a unity gain buffer (op amp with gain=+1), or you might not need one, depending on your source and load resistances.
EDIT: Note that this won't work if your source is AC-coupled.

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Ron (aka Rube)