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Hot!Biasing MCP6S91 Programmable Gain Amp

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Ted M
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2018/10/26 05:15:52 (permalink)
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Biasing MCP6S91 Programmable Gain Amp

I have a design that uses a MEMS analog microphone that I want to feed into an ADC for sampling.  The requirement changed to include the need to have automatic gain and I added the MCP6S91.  The question is about the best (lowest power) way to bias it so that the output is centered around 1.5 volts (Vdd is 2.9 V).  The schematic is attached and Mic_In is the output feeding to the ADC.  Any comments on how it might be improved are welcomed.
 
Thanks in advance.

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    Ted M
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    Re: Biasing MCP6S91 Programmable Gain Amp 2018/11/07 08:54:44 (permalink)
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    If there's a better way to connect it, it's not necessary that the Amp is non-inverting.  The aim is for lowest power while allowing variable gain with the output centered on +2.9V/2 = 1.45V
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