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Multisim and Ultiboard
MOSFET shows higher power consumption than expected
Dear all,
I appreciate if somebody help me to find the rabbit lost in the hat. I designed a half wave rectifier by using a P-channel MOSFET instead of a rectifier diode. The target is efficiency. However, it is not the case with my design due to excessive power consumption of MOSFET in the simulation which is around 2W @ 2 A. I used ideal 4-pin device.
- Channel-A in the first picture is drain current which is measured across 0.01ohm resistor. The peak current while MOSFET is ON at steady state is 2.7 A
- Channel-B in the first picture is Vds which is 0.92 V while MOSFET is on at steady state
- Second picture shows Vout and Vg switching waveform. MOSFET is OFF when Vg is high (36 V)
Multisim shows 1.9 W power consumption in steady state. It should be determined by Rds(ON) in simulation. I cannot understand/explain why there is 919 mV drop on the MOSFET while it is ON.
Any idea?
Best regards!
Hello ihartavi,
Would you mind attaching your file here? Having your original schematics lowers the threshold for looking at it and trying to understand it.
