Hello
I would like to get some design ideas for a PSD (Position Sensitive Device) pre-amplifier. That is the circuit responsible for converting the photo current from the PSD to voltage.
And if possible to have the pre-amp to attenuate DC and low frequencies ( < 5000 Hz).
I have two solutions (in ASCII graphics):
(alt. 1)
|| .---||----. .---. i2_in | || | | |---- | | | | | ___ | +5V | | o--|___|--o ----|PSD| | | | | C1 | | | | i1_in || | |\\| | | |-------o- -||--o--|-\\ | '---' | || | >---o---- Vout .-. .--|+/ | | | |/| R1| | | '-' | | === | GND | | === GND
(alt. 2)
.---. i2_in | |---- | | +5V | | ----|PSD| | | | | i1_in |\\ | |-------o---------|+\\ '---' | | >-----o----Vout | .---|-/ | .-. | |/ .-. | | | | | | | | | | '-' | '-' | | | | '------------o === | GND .-. | | | | '-' | | | --- --- | | | === GND
Which would be the best solution? Or is there some more simple alternatives?