current source design in nA range

[mchak]

hello

I want to design a current source in nano amp range from a reference current source. But the mos is entering in the subthreshold region in order to flow nA range current. I am using GPDK-180 nm technology model file. Is there any option to avoid the subthreshold condition for the mosfets?
can you tell me what is the minimum current to drive the mosfets in saturation region for this technology.

Thanks

 

[apolama]

What type of circuit are you using? Beta multiplier?

 

[vlsi_int]

hello

I want to design a current source in nano amp range from a reference current source. But the mos is entering in the subthreshold region in order to flow nA range current. I am using GPDK-180 nm technology model file. Is there any option to avoid the subthreshold condition for the mosfets?
can you tell me what is the minimum current to drive the mosfets in saturation region for this technology.

Thanks

are you using some sort of current mirror?

 

[mchak]

I have tried with the self biased high swing cascode current source taken from the book "CMOS Analog Circuit Design" by Phillip E. Allen, Douglas R. Holberg.