[sdiy] CV mixer trouble

[Neil Johnson]

On 15/05/2012 22:03, Neil Johnson wrote:
> If the op-amp is a FET type, e.g., TL072, then the bias currents are so
> small as to be worth it (typically 60-100pA).

*Ahem*

That should say:  "small as to NOT be worth it".

Some numbers: lets say 100pA.  Lets also say the impedance seen by the 
-ve pin is 50k (100k || 100k).  Voltage due to bias current is 5uV.

Neil
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