Hi all,

I have a peak detector which gives me the signal level (Vin), but even without a signal, it outputs a DC voltage (Voffset). So the output is Vin+Voffset. Now I want to accurately compare Vin with a reference voltage, Vref. So i need some way to remove VOffset, or add Voffset to Vref. Anybody got any ideas?

thanks,
Aaron

Why not a comparator with switched capacitor methods to store the offsets?

If it is a sampled time system that works well.

Otherwise, AC coupling thru the signal of interest (if you can define the spectrum, or is this truly a DC system?) is a possible, a dummy peak detector with no signal applied to provide an equivalent zero signal offset and op-amp differencing the two is possible, or a feedback system to remove the DC offset is another possibility.

Lots of options.