I have created a circuit in LTspice to switch between two power sources (10s Li-Ion batteries).
V1 and V3 resemble the power sources which vary from 30-42V. V2 and V3 are output pins of an µC. R3 is a the load.
U1-8 are BBS3002 PMOS with pin1=Drain, pin2=Gate, pin3=Source
V1=42V, V2=0V, V3=30V, V4=3.3V --> Pd in U1= 8.1 KW
I think it is due to the low voltage drop over U1 and U4, which will open the PMOS in this spice model, altough threshold is at least -1.2V.
Can someone explain to me, what is happening here ?
edit: added PMOS specs (sorry for bad symbol, this is the model from On Semi)