Electronics - Bipolar Junction Transistors (BJT) - Discussion

Can anyone explain me the difference between collector-base and base-collector?

Hey why not collector emitter?

Please explain why only CB configuration is considered?

@Neha you are right you brief nicely. But I will say in question not mention which types of region of transistor they are asking that is why friends are confused am I right?

It cannot be said base-collector because negative terminal is probed to collector which is to be suffixed first and this rule is obeyed for both PNP and NPN transistor. For PNP transistor (under normal operating conditions) collector- base junction is reverse bias and negative terminal is probed with collector therefore it is to be named first while in NPN transistor positive terminal is probed with collector (which is of N-type) and thus suffixed first.

What is the difference between base collector and collector base?

Hey. What will be the diff b/w base collector and collector base?

To drive a transistor in active region We should make CB reverse biased (along with EB forward bias) so that we intending stop the flow of carriers from collector to base that is reverse biasing the collector to base (this is general for both NPN & PNP transistors). For this we make sure that of circuit configuration is in such way that collector at low voltage and base at high voltage in PNP transistor and this will be reverse in NPN transistor.

This answer is correct only for common base configuration. If we use common emmiter then collector-emmiter will be reverse biased.

In NPN Transistor,

Base - Positive, Emitter- Negative, Collector- Negative

To operate Transistor properly i.e., in active mode

BE junction - forward biased
CB junction - reverse biased