Way to increase output resistance of the amplifier without cascodes

[tyanata]

I, have such a prolem I have to design amplifier at 0.35 technology which has to work from 2 to 3.6 V. At 2V it is imposible to place any cascodes in the circuit. And my question is there eny way to increase output resistance of the amplifier without cascodes?

 

[laglead]

Re: Low voltage Op Amp

Please try local feedback to boost the output resistance.

 

[wenadinho]

Re: Low voltage Op Amp

increase the L of the o/p transistors by at least 5 - 10 times. but it'll reduce phase margin for 2 stage amplifier topology.

 

[mince]

Low voltage Op Amp

You could probably get a folded cascode to work with 0.35u at 2V. Shouldnt really be a problem with an overdrive voltage aroudn 100-125 mV.

 

[qiushidaren]

Low voltage Op Amp

Try gain-boosting technology by using feedback. There are plenty of relevant IEEE papers.

 

[beckchm]

Re: Low voltage Op Amp

when voltage is below 1.2 , cascode is a big problem

there is no headroom to design

2v is enough to include cascode