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Offset Cancelling

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8 Threads found on edaboard.com: Offset Cancelling
Hi, You ask "what is it ? and why is it done ? and how ? and does it differ from an ADC type to another ?" Generally "calibrating" means cancelling or reducing errors. Those errors can be "offset, gain, thermal drifts, linearity..." Klaus
Electret mic has a FET inside, so the gain is proportional to the load resistance, which also affects DC offset from V+ {but out want mic out =V+/2} Modern sound chips often have 0~30dB of gain and so dc offset in the amp, pop filtering, noise cancelling properties and low frequency rejection are all important. Single transistor
I've found a good solution for my problem: I couldn't expect that I can totally decrease the mismatch-effect. But that's not necessary. The mismatch by the layout or whatever leads to an Input-offset which I'm cancelling now by an additional external circuit. The decision-threshold is just shifted. What is causing the mism
The first thing u should cancelling offset of opamp and bias one in condition with maximum gain. How to do this see cadence white paper "Cadence - Functional Verification of a Differential Amplifiers.pdf" on PLZ Don't forget to push the help button if u think i help u.
Now I am simulating a zero IF mixer with the DC cancelling loop circuit, but I am not clear how to simulate the DC offset. The RF frequency is about 2GHz. Need your suggestion!!!
Comparing these two figures, I think you want to cancel the offset voltage of preamp and latch. but for conventional latch, when the latch works on 'nonlinear' . . when the switch is 'on' and the latch is in 'reset', the latch output is all vdd(or a common mode voltage), so the input voltage opamp reset to vdd, the capacitors have not storage any
I think the effect of the preamp on reducing input offset is dependent on its gain.However, since GBW is fixed, preamp will actually not play this role in high-speed applications.Other ways for cancelling offset should be used.
8) you can trim the offset using a potentiometer from the ofset pin. which op amp are u using