Simulation of MOSFET Body Diode

mosfet

Screenshot:
https://onedrive.live.com/redir?resid=DB0189AA1CD22777!451235&authkey=!AAv27e57Imy5LsY&v=3&ithint=photo%2cpng

and a link to the live simulation:
http://everycircuit.com/circuit/6287241984868352

I have been told there is a body diode inside however my simulation shows power travelling from drain to source and vice versa. I thought there was a body diode inside that would only allow for current in one direction.

Best Answer

A common way to draw a MOSFET is by using this or similar images:

enter image description here

As you can see, the body diode is like an internal parallel diode between drain and source. It is functioning as a diode there, no matter what state the MOSFET is in.

If you now apply a sufficient voltage to the gate, the source-drain path starts conducting in both directions.