I should design an opamp transimpedance amplifier as homework, but i
> have some doubts:
> 1) if current signal is an impulse (of positive value) generated every
> 10ms (for example), is it right to put the first pole of open loop
> gain at frequency higher than (1/10)KHz?Or i shoud put the first pole
> at frequency higher than 10(1/10)KHz (so the phase margin is equal to
> 180=B0)? I'm interested on voltage output (bacause this should be read
> by an ADC)...
Ignore the "how often" look at the "sharpest corner". The frequencies you need to work with include all that are needed to make the output waveform.
2)If i want to design an opamp with single supply, other problems
> (respect to bipolar supply) are present or not?
> Thanks
Single supply op-amps are just ones that work with their inputs and output near the minus supply. PNPs on the input section can be used to get there. Take a look at the first stage of the LM324.