mos operation regions

[vead]

there are three regions of operation in mos transistor
1. cut off
2. linear
3.saturation

consider cmos Inverter circuit
Input is high -> output is low
pmos in cut off -> nmos in linear

Input is low -> output is high
pmos in linear ->nmos in cut off

I am having problem to understand last condition '' saturation "
how transistor work in saturation work

 

[duke37]

Saturation is when the transistor is turned fully on like a switch. The current through it is controlled by the external circuit.

 

[(*steve*)]

Where you write "linear" in your explanation of a mosfet, you really mean "saturation".

The transistors in a digital circuit spend as little time as possible in the linear region, they are either on (saturated) or off (cutoff).

 

[vead]

Where you write "linear" in your explanation of a mosfet, you really mean "saturation".

The transistors in a digital circuit spend as little time as possible in the linear region, they are either on (saturated) or off (cutoff).

transistor are either on (saturated) or off (cutoff).

so what happen when transistor in linear mode
transistor will be on or off

 

[LvW]

I think, there are no "digital parts". Rather we have parts which mostly are operated between two extreme conditions ("digital") or any where in between.
That means: We shouldn´t only distinguish between "on" and "off". A ggod example is the CMOS inverter which can be (and is in some applications) operated in a quasi-linear mode.

 

[(*steve*)]

so what happen when transistor in linear mode

In a digital circuit this means it is actively switching (or it's being forced not to be digital as in the case mentioned by LvW above).