Hi
I am Henry and we were setting up AFE5804 in our lab in college. We have a query in the CW path gain.
The LNA gain is 20dB (gain of 10 V/V) . The transconductance of the V2I amp is given as 13.8 mA/V (current output). We are using a external I2V in which the CW output current flows through 200 ohm. So the gain we were expecting was 10*13.8m*200 ~= 28. But we are seeing a gain of 3.
The query is that whether the signal flow assumed above is correct. If we assume that the LNA itself becomes the transconductor(V2I) then the numbers are matching. 13.8mA/v*200ohm ~= 3 (V/V) . The currents in the 8 channels are also summing properly and giving 8 times the individual channel gain.
In other words, the query on the signal flow in the channel is that whether : input voltage->V2I(13.8mS)->current output (or)
input voltage->LNA(10 V/V) ->V2I (13.8mS)->current output.
Thanks
Henry
