Hi, I'm looking to attach a load to the AC_Shield pin of the AD7147 device that exceeds the 150 pF max value specified in the data sheet. I plan on using a buffer amplifier to address this issue. Is there a minimum bandwidth that the amplifier must have in order to properly buffer the signal? I'm concerned that if an unsuitable buffer amplifier is chosen, the buffered AC_Shield signal won't actually be able to be used for shielding purposes (due to a time lag introduced by buffering and/or distortion of the square wave).
Here's the buffer I am currently thinking of using:
Do you think this will work? Or do you recommend something different?
The AC_SHIELD output is 250kHz, so the buffer does not need to be particularly wide band.
I'd recommend the ADA4891 op amp, its available in a SOT23 , and has the required slew rate and low input capacitance.