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two port device with a linear i-v characteristics

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hi,
is it possible to build a two port circuit with highly linear i-v chararacteristics? actually we call them resistors in everyday life, but i want this circuit to be consisting of only MOS transistors. is such a circuit practical? also, what do we call such circuits?

by the way, a MOS transistor is highly linear for small values of Vds (if Vds<<2(Vgs-Vt)). but i want this linear behaviour to be extended to higher values of Vds.

any idea?

(is this question too elementary or what?)
 

We usually use the output impedance of a MOSFET current source in Integrated Circuits when a resistance is required b/c fabricating an actual resistor is expensive in terms of chip area and also not very accurate.

Thus ΔI = ΔV/Rout

i.e. when you vary the voltage at the output of the current source, the current varies linearly (riding on an offset value).
 

zeeshanzia84 said:
We usually use the output impedance of a MOSFET current source in Integrated Circuits when a resistance is required b/c fabricating an actual resistor is expensive in terms of chip area and also not very accurate.

Thus ΔI = ΔV/Rout

i.e. when you vary the voltage at the output of the current source, the current varies linearly (riding on an offset value).
Click to expand...

thanks for your reply, but is it possible to get rid of that offset value you have mentioned?
 

Yes, but not using the current source only.
b/c we are using a current source that has a particular DC output. The ΔI can be regarded as a signal o/p to a ΔV change. The current source DC o/p (offset) is a DC bias (which must be present for a trasistor based circuit to work)

However you can design a simple offset nulling circuit using a Differential Amplifier.
 

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