Contents
- 1 Are BJT and MOSFET interchangeable?
- 2 What are the main constructional difference between a MOSFET and a BJT?
- 3 What are the main constructional differences between a MOSFET and a BJT what effect do they have on the current conduction mechanism of a MOSFET?
- 4 Why is CMOS better than BJT?
- 5 Why is FET better than BJT?
- 6 What is difference between Transistor and FET?
Are BJT and MOSFET interchangeable?
In general we can easily replace a BJT with a MOSFET, provided we take care of the relevant polarities. For an NPN BJT, we may replace the BJT with a correctly specified MOSFET in the following manner: Remove the base resistor from the circuit because we don’t typically need it anymore with a MOSFET.
What are the main constructional difference between a MOSFET and a BJT?
Differences between BJT and MOSFET
| BJT | MOSFET |
|---|---|
| The input impedance is low | The input impedance is high |
| The switching frequency of BJT is low | The switching frequency of MOSFET is high |
| It is used for the low current application | It is used for the high current application |
What are the main constructional differences between a MOSFET and a BJT what effect do they have on the current conduction mechanism of a MOSFET?
A BJT has an emitter, collector and base, while a MOSFET has a gate, source and drain. 3. BJTs are preferred for low current applications, while MOSFETs are for high power functions.
Is BJT better than MOSFET?
Parasitic capacitance in BJT is less when compared to MOSFET which makes it faster whereas MOSFET being a majority carrier device switches faster than BJT.
Why MOSFET is preferred over BJT?
They are portable, use low power, draw no current and are compatible with silicon processing technology. Their lack of gate current results in high input impedance. One additional major advantage of MOSFET over BJT is that it forms the basis of a circuit with switches of analog signals.
Why is CMOS better than BJT?
mosfet is much faster than bjt because in a mosfet, only majority carriers are the current. mosfet has a very high input impedance in the megohms range while bjt in the kiloohms range . thus making the mosfet very ideal for amplifier circuits. mosfets are less noisy than bjts.
Why is FET better than BJT?
It is a high input impedance device about 100 MOhm and above. FET has no offset voltage when used as switch unlike BJT. FET is relatively immune to radiation but BJT is very sensitive….FET.
| BJT | FET |
|---|---|
| Low current gain | High current gain |
| Low input impedance | Very high input impedance |
| Low output impedance | High output impedance |
What is difference between Transistor and FET?
The major difference between BJT and FET is that in a field-effect transistor only majority charge carries flows, whereas in BJT both majority and minority charge carriers flow….Difference between BJT and FET.
| BJT | FET |
|---|---|
| BJT gain is more | FET gain is less |
| Its output impedance is high due to high gain | Its output impedance is low due to low gain |
Why are MOSFETs preferred over BJT?