Junus2012
Advanced Member level 5
Hello Analog heroes
I finished design of an NMOS input OTA, I used a cascode current source and I was expecting to get bad low ICMR, but I surprised with the result. as you can see the cascod current source start to saturate at 2.3V while the ICMR start showing linear behavioural at 0.25V. then I did the ICMR test by sweeping the VCM from the A.C analyses as shown in the second image, the result always the same
What are the reason behind that?
![](https://obrazki.elektroda.pl/8744706800_1352555579_thumb.jpg)
![](https://obrazki.elektroda.pl/7397826500_1352556045_thumb.jpg)
Thank you very much
I finished design of an NMOS input OTA, I used a cascode current source and I was expecting to get bad low ICMR, but I surprised with the result. as you can see the cascod current source start to saturate at 2.3V while the ICMR start showing linear behavioural at 0.25V. then I did the ICMR test by sweeping the VCM from the A.C analyses as shown in the second image, the result always the same
What are the reason behind that?
![](https://obrazki.elektroda.pl/8744706800_1352555579_thumb.jpg)
![](https://obrazki.elektroda.pl/7397826500_1352556045_thumb.jpg)
Thank you very much