On Thu, Aug 9, 2012 at 8:10 PM, Spehro Pefhany <speff@interlog.com> wrote:
> At 03:25 AM 09/08/2012, you wrote:
>
>
>>The OA which do the sum can do an x10 sum as well.
>>The repeater after the 4K7-500-5k1 may dissapear if the resistor at
>>the noninverting input is 10x greater than the impedance of resistor
>>network above.
>
> Umm.. if a 10% gain error is acceptable...

Often it is, since he didn't mention. Less than 5% is possible.
--=20
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