[sdiy] Single supply opamp as inverting summing amplifier

[Ken Stone]

Yes. Add an electro across the bottom resistor - 10 uf for example.

Ken

>An analog question in a digital age ... ;)
>
>I'm designing the front end for an audio CODEC.  I'd like the whole 
>thing to run off a 5V supply (well 2x 5V supplies really - 1 digital, 1 
>analog), so I'm using AD823 opamps which are pretty good for audio and 
>can swing very near both the positive and negative supply rails.
>
>So, I have an AD823 wired as an inverting summing amplifier to sum the 
>different inputs together.  The + input then needs to be at 2.5V.  So 
>should I just make a potential divider between 5V and 0V?  This seems 
>like it might introduce noise from the power rail.  Is there a standard 
>trick used in this kind of situation to get the signal to float between 
>V+ and 0V?
>
>TIA,
>Seb
>
>
>
>
_______________________________________________________________________
Ken Stone   sasami at hotkey.net.au or sasami at cgs.synth.net
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>