Russell wrote:
> If you can add a "whisper" of negative supply to opamps like this then 
> you can swing to true ground. Even a few tenths of a volt will do. 
> This can be accomplished with eg a simple diode pump driven from just 
> about any available signal.
> 
> Another "naughty" but potentially (pun vaguely intended) trick is to 
> place a Schottky diode in the ground lead of the power supply. 
> Decouple this well (large cap across the diode and also a small 
> ceramic). Take negative opamp supply rail from diode cathode and 
> system ground from diode anode. This gives you a Schottky diode 
> voltage drop (typically a few tenths of a volt) as the opamp negative 
> supply. Voila - true ground output. This method has its potential 
> "problems" but may well be perfect in your application. This of course 
[snip]

Thanks, I will definitely keep this trick in mind!

Best regards,

Vitaliy

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