[SOLVED] op amp circuit grounding question

[obrien135]

http://www.datasheetcatalog.org/datasheet/nationalsemiconductor/DS006739.PDF

The above link is to a pdf file of a data sheet for a LM675 op amp. The typical applications circuit diagram near the top of it shows a 1 ohm resister in series with a 0.22uF capacitor going to ground. I used a single supply voltage and used a zener diode circuit to provide the "ground" for the 1kohm resister. But unfortunately I erroneously connected the 0.22uF capacitor to the negative supply instead of the zener cathode. I was wondering if, since in a transister circuit such as a common collector the collector is in effect connected to ground for ac purposes, if the same thing would apply here and hence it would be OK to leave the 0.22uF cap connected to the negative supply. I think it might have something to do with thevinizeing a circuit where you consider all dc supplies to be a short to graound ( when finding the thevinin equivelent impedance). Am I completely incorrect about this?

George

 

[FvM]

The RC circuit (also called boucherot cell or zobel network) should be connected across the load, respectively to a low impedance ground, not a virtual ground. The negative supply should be O.K. as well.

A zener diode virtual ground should be bypassed sufficiently, otherwise it must be feared to cause distortions.