Bias the analog input - AD2

[Alessandro]

Good morning to everyone,

I'm doing an experiment in which I sample the 2 analog input scopes of the Analog Discovery 2 at every iteration of a for cycle. At these analog inputs I analyzed the current coming from to 2 photodiodes. There is a order of magnitude between the 2 measured voltage (current of the photodiode*AD2 input resistance) meaning tens of mV for 1 photodiode and hundreds of mV for the other photodiode.

The problem with this kind of measure is that the response of the 2 photodiodes to a power ramp is different. This could depend on the fact they are unbiased.
Therefore I'd like to bias directly the 2 analog inputs. Is it possible o I need to insert a transimpedance amplifier between the photodiode and the analog input?

Thank you in advance,
Alessandro

[attila]

Hi @Alessandro

Yes and you can use FDwfAnalogInChannelAttenuationSet to specify the amplification (1/att) so the read voltage data is scaled correctly.

[Alessandro]

Hi @attila,

if yes, what is the python line that I should write to force a 2V into the analog input? Thank you

Alessandro