Ideal diode used as relay?


Solar Enthusiast
The more I look at the AliExpress picture the more confused I am. If this is actually an N-channel IPT015N10N5 MOSFET why is it shown here as a high side switch? The Drain is labelled Out(+) and the Source is labelled In(+)! In that case wouldn't it simply conduct via the MOSFET body diode? What am I missing here? My electronics knowledge is limited at best.

EDIT: I was expecting the usual AliExpress shenanigans but I realized that if U1 is able to drive the gate higher than the source voltage the NPN can be driven as a high side switch. That makes these a pretty good deal given that it's a $10 MOSFET!
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Solar Addict
The module may be using 300A rating MOSFET but the way the module is made, it is using PCB copper plane as heatsinnk and that is why it shows: it is a false claim of 300A handling module.
This needs to be repeated....and explains the failure at below rated capacity of my trigger switch, a burnt board but still operational.
Without a proper heat sink they will smoke


Solar Addict
This will act like a relay + an ideal diode, preventing reverse current.
A plain MOS-FET will conduct on reverse current, more likely it will burn through...

Bud Martin

Photon Sorcerer
The module in OP link, It is not acting like relay because the current is still flowing through the Body diode of the N-CH MOSFET even though the MOSFET is not turned on.
Input post is connected to the Source (Anode of the Body diode)
Output post is connected to the Drain (Cathode of Body diode)


Solar Addict
Another ad for one popped up with a warning to connect negative first.

Important note 1: in the installation, be sure to connect the line first to the electricity. If the battery can not be cut off, when wiring, must first ground wire, then connected to the output positive, and then connected to the input positive.


Solar Enthusiast