What is PNP Transistor and working principle

PNP Transistors:

Symbol

The symbol for a PNP transistor also has three terminals: the emitter (E), base (B), and collector (C). The arrow on the emitter leg points inward, indicating the direction of conventional current flow (from positive to negative).
 
Applications:

•  Used in the same applications as NPN transistors but with opposite polarities.
•  Ideal for low side switching, where the load is connected to the positive supply.

Working Principle

PNP transistors are composed of two p-type (positive) semiconductor materials separated by a thin layer of n-type (negative) material. The three regions are:

- Emitter (E): Heavily doped p-type material that emits holes.
- Base (B): Thin, lightly doped n-type material.
- Collector (C): Moderately doped p-type material that collects holes.

When a small current flows out of the base (B), it allows a larger current to flow from the emitter (E) to the collector (C). The holes from the emitter diffuse into the base, where they recombine with electrons. The thin base region allows most of these holes to reach the collector, creating a larger current flow. PNP transistors operate similarly to NPN transistors but with reversed polarity, making them suitable for different