Tool/software:
Hello there,
We have a project that fully relies on the fact that the In_Aux path has a > 20MHz bandwidth, using the BUF802 in CL mode/
As our board wasn't behaving as expected, we removed the DC blocking capacitor to IN (and also tried shorting in to GND) and measured:
- our input to output transfer function (from our differential inputs to the BUF802 output) - green trace in the attached file
- our input to IN_AUX pin input transfer function (from our differential inputs to the BUF802 IN_AUX pin) - red trace in the attached file
Unless I'm mistaken, we're seeing our IN_AUX driving opamp (ADA4806, 105MHz GBW) starting to compensate the gain loss at <10kHz, to finally "run out" of GBW product at 2MHz.
Hence my question: why would our opamp start increasing gain at around 10kHz if the IN_AUX path bandwidth truly was 800MHz? How was this 800MHz measured?
Thanks in advance
