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Comparison between BJT and MOSFET

Sr#

Bi-Polar Junction Transistor (BJT)

Metal Oxide Field Effect Transistor (MOSFET)

1

It is a Bipolar Device

It is majority carrier Device

2

Current control Device

Voltage control Device.

3

Output is controlled by controlling base current

Output is controlled by controlling gate voltage

4

Negative temperature coefficient

Positive temperature coefficient

5

So, paralleling of BJT is difficult.

So, paralleling of this device is easy.

6

Dive circuit is complex. It should provide

Dive circuit is simple. It should provide

7

constant current (Base current)

constant voltage (gate voltage)

8

Losses are low.

Losses are higher than BJTs.

9

So used in high power applications.

Used in low power applications.

10

BJTs have high voltage and current ratings.

They have less voltage and current ratings.

11

Switching frequency is lower than MOSFET.

Switching frequency is high.
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