Current to Voltage Converter design issue

Hi, At the URL:

formatting link
there is some theory for a standard OP Amp based I/V converter. When using a capactive sensor, is it possible to cancel the low pass filter instability effect mentioned (due to Rf, Cs) by another method, instead of placing Cf across the feedback resistor? Im looking for a way of restoring stability without reducing the bandwidth or gain of the circuit. I had initially thought of some sort of current mirror buffer between the feedback resistor and the non-inverting input, so the feeback resistor is not fully presented to the sensor, and therefore the introduced low pass action is minimised.. Comments please. regards, JEFF

Reply to
Loading thread data ...

Current-mode opamps have inherently low input impedances on the inverting input. That will help stability, but may well trash noise and dc performance.

Phil Hobbs addreses the photodiode tia situation in his book, and I think he has some stuff on his web site as well.


Reply to
John Larkin






Reply to

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.