What is the main function of a PNP transistor?

A PNP transistor primarily functions as a current amplifier, making it suitable for amplifying small signals. In the context of a PNP configuration, the transistor allows current to flow from the emitter to the collector when the base is pulled low relative to the emitter. This characteristic is utilized in various applications, including audio amplification and signal processing, where weak signals need to be increased to a level that can drive other components or stages in a circuit.

The PNP transistor's ability to increase current makes it integral in electronic circuits where signal integrity and strength are crucial. Additionally, while transistors can be used for switching applications, their core function and efficiency lie in amplification rather than solely switching or acting as passive components like resistors.

In summary, the defining capability of a PNP transistor is its role in amplifying small signals, which allows it to effectively boost the power of the input signal into a more usable form.