What is the use of resistor R95 in the transistor control circuit?

西里古1992

What is the use of resistor R95 in the transistor control circuit? [Copy link]

It can be turned on without adding it. I used multisim to simulate it with and without the pull-down resistor, and it both worked. Could it be that the driving capability is increased? It seems that the voltage is lower after it is turned on?

Kkk-

Bias resistor.

maychang

"What is the use of resistor R95 in this transistor control circuit?"

After adding this resistor, the anti-interference performance of the circuit will be better than without this resistor, and the temperature stability will also be better.

gmchen

This resistance does not really play a big role under static conditions, but it plays a big role in the dynamic process of the transistor.

When the transistor in the figure works in the switching state, due to factors such as working reliability and device versatility, its on state is often designed to be overdriven, that is, the base current is greater than the actual required current. In this case, when the transistor is turned on, carriers will be stored in the base region, and when it is turned off, the turn-off delay will increase due to the carrier storage effect. After adding the resistor R3, the carriers in the base region obtain a release channel, which can increase the turn-off speed.

If you use a square wave drive to simulate, you can see that adding or not adding this resistor makes a difference in the delay of the leading and trailing edges of the square wave.