NPN Transistor vs PNP Transistor?

A transistor is a semiconductor device that can amplify and switch electronic signals.

NPN Transistor vs PNP Transistor

Generally, 2SA and 2SB are part numbers for PNP transistors, while 2SC and 2SD are part numbers for NPN transistors. The letters and numbers in the part numbers refer to different characteristics and specifications of the transistor.

The main difference between these two types is the direction of current flow in their base, emitter, and collector regions.

npn transistor vs pnp transistor

Basic differences

1. NPN Transistor:

In an NPN transistor, the current flows from the emitter to the collector. To turn on the transistor, a small current is applied to the base, which allows a larger current to flow from the collector to the emitter. The base region of an NPN transistor is doped with a material that has fewer electrons than the emitter or collector regions.

Part numbers of commonly used NPN transistors:

(1) BC547 – NPN general-purpose transistor ( 45V, 100mA )
(2) BC337 – NPN general-purpose transistor
(3) 2N2222 – NPN switching transistor ( 40V, 0.5A )
(4) 2N3904 – NPN general-purpose transistor ( 40V, 200mA )
(5) PN2222 – NPN small signal transistor
(6) MPSA42 – NPN high-voltage transistor for switching and amplifier applications
(7) TIP120 – NPN Darlington transistor for high current applications

2. PNP Transistor:
In a PNP transistor, the current flows from the collector to the emitter. To turn on the transistor, a small current is applied to the base, which allows a larger current to flow from the emitter to the collector. The base region of a PNP transistor is doped with a material that has more electrons than the emitter or collector regions.

Part numbers of commonly used PNP transistors:

(1) BC557 – PNP general-purpose transistor ( -45V, -100mA )
(2) BC327 – PNP general-purpose transistor
(3) 2N3906 – PNP switching transistor
(4) 2SA970 – PNP audio frequency transistor
(5) S8550 – PNP transistor for high-voltage applications
(6) MPSA92 – PNP high-voltage transistor for switching and amplifier applications
(7) A1015 – PNP general-purpose transistor ( 2SA1015 Transistor – 50V, 150mA )

Datasheet of NPN 2N3904 vs PNP 2N3906

npn 2N3904 pinout

pnp 2N3906 pinout

2N3904 Datasheet PDF

LM324N pdf

2N3906 Datasheet PDF

2N3906 pdf

FAQs:

Q: What is the main difference between an NPN and PNP transistor?
A: The main difference between an NPN and PNP transistor is the direction of current flow in their base, emitter, and collector regions.

Q: Which type of transistor is more commonly used?
A: NPN transistors are more commonly used because they are easier to manufacture and have better performance characteristics than PNP transistors.

Q: What are some applications of NPN and PNP transistors?
A: NPN and PNP transistors are used in a wide range of electronic devices, including amplifiers, switches, oscillators, and voltage regulators.

Q: Can NPN and PNP transistors be used interchangeably?
A: No, NPN and PNP transistors cannot be used interchangeably because their pinouts and characteristics are different.