maggio 06, 2019
2905
1. Compared with the current-controlled triode, the
MOS tube is voltage control, which can be understood as a change from analog to
half-number. In the switch state, it is a number, in the amplified state,
similar to a half-number;
2. Due to the current-controlled triode, there will
be a common current path between be and ce, so there is no isolation; MOS tube
can be considered as quasi-isolated state, no common current channel; but need
to pay attention to MOS tube After breakdown
Form a public passage, the hazard at this time
should be analyzed, and the design should be considered in advance;
3. On the switching speed, due to the no current
decay process, the speed is also improved a lot with respect to the triode,
generally 100KHz can be satisfied;
4. Due to the above characteristics, and the
on-resistance Ron of the MOS transistor is already relatively small, the power
consumption is obviously superior to the triode, so many occasions have begun
to gradually replace the triode;
5.p-type mos tube, low level conduction, high level
cutoff; n-type mos tube, high level conduction, low level cutoff; different
types of MOS tubes are used in different occasions, but need to consider N type
MOS There are many types of tubes to choose from, the price is low, and the P
type is small, so it should be considered comprehensively when using it;
6. MOS tube heat dissipation, when selecting, not
only to see the current through the satisfaction, you must consider the heat
problem, especially in the case of high current, heat dissipation needs to be
careful, because heat dissipation is a process of continuous deterioration,
high temperature, resistance Large, high resistance, higher temperature, so
heat dissipation requires special attention. Considering that the heat
dissipation and installation process are closely related, it is best to use the
thermal infrared to measure the product when it is actually working for a long
time. In the limit state, there is a certain margin.
The above is a rough understanding of the MOS tube,
please correct me.
