Martin K wrote:
> I have a circuit here that uses a TLE2426 
> (http://focus.ti.com/lit/ds/symlink/tle2426.pdf) "rail splitter" to 
> provide a virtual ground for an opamp circuit. I was/am having trouble 
> with it because it was actually creating the ground at about 3/4*(Vin). 
> The overall load is close to 1mA going into the virtual ground.
>
> So I was there trying to troubleshoot the problem. I accidentally 
> slipped with the osc. probe and shorted the output to -Vin for a 
> fraction of a second. I noticed that the output came back immediately to 
> where it should be (1/2*Vcc). I can repeat this over and over. Remove 
> power, reapply, short it to ground for a second, and it ends up where it 
> should be. I thought it might be oscillating but I don't see any 
> oscillations. The datasheet doesn't seem to say anything about such a 
> problem. Do you know what my issue (with the circuit) might be?
>
> Thank you
> -
> Martin K
>
>   
I've made the situation a bit better by placing a 10uF ceramic on the
input and output (output to -Vin). I think I've compounded the problem
by running a LDO from +Vin to virtual ground to output 5v - I needed 5v
regulated from a divided 10-14v battery supply, and the ability to power
bipolar opamps. So with no load there doesn't appear to be any oscillation.
Thanks for the advice everyone.
-Martin
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