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MOSFET ORing circuit simulation (LTspice)

udhay_cit

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Hi,
My LTspice circuit simulation for MOSFET power supply ORing circuit is blocking the reverse conduction?
Still I didn't tried this circuit practically. Now I need to use this circuit for one of my project and I did the simulation first.
Unfortunately the MOSFETs are conducting in reverse direction and not working as per my expectation.

Any one used this type of circuit in real time application? Why the MOSFETs are conducting in simulation? Am I doing anything wrong?

Udhay
 

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KlausST

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Hi,

Why do you think there is a reverse current protection? I can´t see.

Both MOSFETS are ON, because both V_GS is beyond the threshold level.

My recommendation:
Look for "ideal diode" circuits.

Klaus
 

d123

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Hi,

To me, it looks like two parallel PMOS, and that seem to be backwards wrt their respective power supplies, so they'd always conduct. Could be pesky body diodes.
 

crutschow

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the MOSFETs are conducting in reverse direction and not working as per my expectation.
What is your "expectation" of the circuit.

That circuit will protect against reverse polarity of the input source, but will not provide a power-OR function.
 

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