Oz-in-DFW wrote:
Chopping is used to cancel DC offsets in imperfect amplifiers, it adds no gain. If there is a DC component and you filter with a cutoff frequency below the chop rate, the offsets of the amplifier can be effectively canceled.
Chopping isn't quite that magical. You chop the DC signal before the first amplifier, and synchronously (usually) detect the amplified signal after the last amplifier. The key benefit to chopped amplifiers is the high gain stages can be AC coupled, which eliminates any DC drifting in the high gain amplifiers from affecting the results. Chopping doesn't cancel any DC offsets that might exist in the input signal, or in the input, or output, chopper mechanism. -Chuck Harris _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
