alan smith wrote:
> Using a MCP4922 as the source with a 4.096VREF, the output ranges as
> expected from 0V to 4.09V
> 
> I followed this with a IS55004 quad opamp, for reasons of needing0-10V
> output.  The voltage on the opamp is 24V.  yes I know I need to adjust
> the gain to 2.44 to get 0-10V...that can be done after it works at 2X
> 
> Just the classic 2X gain of a 10K from the (-) to ground and a 10K feedback,
> is not giving me the expected results.  I put in 4.99K compensation on the
> (+) input.  The output with 0V in, is giving me 1.8V out.  If I ground the
> (+) input, it runs up to 21V.
> 
> So what am I missing here?

A negative power supply on the opamps?
These units do not have rail-to-rail inputs or outputs.

-- Dave Tweed
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