I was looking at this P-channel MOSFET datasheet and I am a bit confused.

Continuous Drain Current and Continuous Source Current

(Source: Vishay Siliconix Si5435BDC Datasheet)

How it is possible to allow for a different current for the source and the drain? The datasheet states more A for the drain than the source. As I get it all the current that enters drain must exit the source. Where the extra current for the drain comes from?

  • 3
    \$\begingroup\$ You're right, that's an odd and confusing way of showing the (lower) acceptable body diode current. Usually it's something more like "Continuous Source-Drain Diode Current IS". Since current can flow in the opposite direction through an 'on' MOSFET it's not even unambiguous. \$\endgroup\$ Jul 17, 2015 at 20:32

1 Answer 1


With source current they mean the current over the body diode. This current flows, when the drain potential is higher than the source potential. Check for example the specification of the diode forward voltage, here Is is mentioned whereas for Rdson Id is mentioned.


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