Nmos transistor floating source node

[mjbreddy]

For an nmos transistor if Vdd=5v, Vin is connected to nmos transistor gate, vdd is connected to the drain and source is left floating (node V01)tell me what are Vo1 when Vin is 5V, 3V, 2.5V and 0V.

 

[crutschow]

Why do you want to know the voltage at a floating node? Is this homework?

Due to drain-source leakage current the floating voltage would likely be equal to Vdd.

 

[varunkant2k]

Hi mjbreddy, you already got correct reply from crushow, when you ask what are Vo1 when Vin is 5V, 3V, 2.5V and 0V.
Another question should be, what would be operating region for transistor across voltage range you specified?
Answer is transistor remain off until Threshold voltage(at gate), and goes to triode region when higher than threshold voltage.
It never goes to saturation.!!!