Hi all,
I'm trying to design an amplification circuit using an OPA835.
My input signal is a 150kHz 0-5mV signal (or -5mV-0 depending on the configuration I use). I want a voltage gain of 600x (56dB), or the best I can have with single rail supply, powering the opamp with a 3.8V 500mAh battery.
Fig.17 of the datasheet tells me that at 150kHz my gain is around 40-45dB, at best. Let's assume that it is fine. I did a simple inverting configuration, and chose R_F=2kOhm as specified on page 31 of the datasheet and, consequently, R_G =3 Ohm.
But I don't see any amplification of AC signals on the output.
Is it ok to chose the two resistors the way I did?
Thank you