i read when we use a transconductance amplifier or current to voltage converter , the output voltage will be the multiplication of negative of input current by feedback resistor. V (out)=-i (in)* R
so for example if we have a 1 nA input current we will have a -0.1 V at the output while the feedback resistor is 100 M ohm. So my question is that why we bother to use an op-amp? i mean why we don't run the current directly through the R?
i read somewhere it is related to power gain but i don't really understand this. can anyone help me out to understand this? please explain somehow that a chemist could understand!
Thanks
so for example if we have a 1 nA input current we will have a -0.1 V at the output while the feedback resistor is 100 M ohm. So my question is that why we bother to use an op-amp? i mean why we don't run the current directly through the R?
i read somewhere it is related to power gain but i don't really understand this. can anyone help me out to understand this? please explain somehow that a chemist could understand!
Thanks