I've been using the AD620 to offset and scale up a tiny AC signal for my project.
The AD620 is set up in the following way:
- Rg= 6.8kOhms (between pins 1 and 8)
- Vin = 0.123V rms AC signal (pins 2 and 3)
- REF = 2.5V (pin 5)
- +Vs = 5V (pin 7)
- -Vs to Ground (pin 4)
Even though the gain is supposed to be G=49.4k/Rg+1=8.26 and I'm supposed to see an output (pin 6) of: V=0.123*8.26=1.02 V-rms, I get no AC output signal at all.
What I'm getting is a DC 1.6 Volts signal (which, I suppose, comes from Vref).
Do you guys have any idea of what's going on?