Difference between output power MOSFET and bipolar output power crystal triode

Nowadays, with the rapid development of science and technology, semiconductors are used in more and more industries, in which the MOSFET is also considered a very common semiconductor device, the next step is to understand what is the difference between the characteristics of the bipolar power crystal transistor and the output power MOSFET.

1, the way of work

MOSFET is the work required to promote the operating voltage, circuit diagrams explain relatively simple, promote the power of small; power crystal transistor is a power flow to promote the program design is more complex, to promote the specification of the choice of difficult to promote the specification will jeopardize the power supply total switching speed.

2, the total switching speed of the power supply

MOSFET affected by the temperature is small, the power supply switching output power can ensure that more than 150KHz; power crystal transistor has a very few free charge storage time limit its power supply switching speed, but its output power is generally not more than 50KHz.

3、Safe working area

Power MOSFET has no secondary basis, and the safe working area is wide; power crystal transistor has a secondary basis situation, which limits the safe working area.

4、Electrical conductor working requirement working voltage

Power MOSFET belongs to the high voltage type, the conduction working requirement working voltage is higher, there is a positive temperature coefficient; power crystal transistor no matter how much money is resistant to the working requirement working voltage, the electric conductor working requirement working voltage is lower, and has a negative temperature coefficient.

5, the maximum power flow

Power MOSFET in the switching power supply circuit power supply circuit circuit power supply circuit as a power supply switch, in operation and stable work in the middle, the maximum power flow is lower; and power crystal transistor in operation and stable work in the middle, the maximum power flow is higher.

6、Product cost

The cost of power MOSFET is slightly higher; the cost of power crystal triode is slightly lower.

7、Penetration effect

Power MOSFET has no penetration effect; power crystal transistor has penetration effect.

8、Switching loss

MOSFET switching loss is not great; power crystal transistor switching loss is relatively large.

In addition, the vast majority of power MOSFET integrated shock absorbing diode, while the bipolar power crystal transistor almost no integrated shock absorbing diode.MOSFET shock absorbing diode can also be a universal magnet for switching power supply circuits magnet coils to give the power factor angle of the power flow safety channel. Field effect tube in the shock absorbing diode in the whole process of turning off with the general diode as the existence of reverse recovery current flow, at this time the diode on the one hand to take up the drain - source pole positive middle of a substantial rise in the work requirements of the operating voltage, on the other hand, and the reverse recovery current flow.