Hi all,

I would like to know if anyone has suggestions for filtering the AC component of a signal. The problem is that the DC component of this AC signal compensates for the fluctuating AC signal. So when I remove this DC component using filtering, then the AC signal shifts up and down.

I thought of using a differential amplifier but my signal has high frequency components of up to 12.5MHz and the op-amps I have aren't fast enough for that.

 

hi Lucky,
Do you have a circuit diagram you could post?
E

 

This is the way output is filtered using AC coupling with a DC bias. This is fed directly to the positive input pin of a comparator. The thing is that the CCD sensor has inherent DC compensatory properties that make sure the signal doesn't fluctuate. But this DC signal is filtered out during AC coupling and thus the signal fluctuates.

 

Hi L,
If you want to blow the fuse when over voltaged you could use a Zener diode to the Gate of a MOSFET, which could apply an effective short across the 12V after the Fuse.
E

 

It is not at all clear which signal or voltage the TS wants to pass and which voltage the TS wants to reject or ignore. Until that is defined there is no point in the request.