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Operating frequency of power MOSFET is higher than that of power BJT. Justify the statement.

1 Answer

Power MOSFET have high turning on and turning off capability high switching speed of MOSFET is due to the high rate of change of drain voltage. The switching losses of power MOSFET is low means MOSFET provide higher efficiency for higher frequency. But the conduction losses of power MOSFET is more. The power MOSFET is the positive temperature coefficient device means as the temperature increases the internal resistance of MOSFET will also increase. The voltage and current rating of power MOSFET is low. The conduction voltage of MOSFET is higher than bipolar.

In case of BJT, the switching losses are more but conduction losses are less. BJT provides more efficiency at a lower frequency. Hence, operating frequency of power MOSFET is higher than that of power BJT.

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