Recent content by mohindar

yes i have already done that reversing that photodiode , but output is same ! main problem is that Cf should discharge with Cf.Rf time constant but here it is discharging within 70ns but in circuit time constant is in terms of us.

thank you for your quick reply. my main doubt is that is it ok to use opa657 for this experiment? and for testing it with ir photodiode ?

oppsss... that is mistake in circuit diagram...in actual circuit i have used +5v and -5v power supply..rest of component according to above post.

can you please tell me where i am making mistake in my experiment ? why its output signal has same pulse width as input signal according to theory output pulse is decaying step signal with RfCf time constant.

here is circuit attached.

hello sir, we are designing radiation measurement readout front-end electronics, as part of our project ,in very 1st step to understand working of CSPA(charge amplifier) i had done little experiment by connecting photodiode with opa657 .here i have used general purpose ir photodiode and Rf=147k...