why does a p-channel JFET differ from an n-channel JFET?

[diaryrashid]

hi...

why does a p-channel JFET differ from an n-channel JFET?

what is the difference between them?

 

[richaphy]

In a n-channel JEFT, the channel is n-type, and gate is p-type that means the majority carriers across the channel are electrons. the opposite is for p-channel JFET where majority carriers are holes. Accordingly the polarities of the voltage supplies change while biasing them. To switch off an n-channel device requires a negative gate-source voltage (VGS). Conversely, to switch off a p-channel device requires positive VGS.
Also n-channel JFET are faster than p-channel, because of higher packing density, and electron move faster than holes, in other words, electron have higher mobility than holes.

 

[Prashanthanilm]

pJFET has hole as Majority carrier.
nJFET has electron Majority carrirer.

Based on the majority carrier charge present, the voltage biasing is done.
Positive voltage is fed to nJFET and Negative voltage is fed to pMOS for operation.