A1972 PDF Datasheet – 400V, PNP Transistor – 2SA1972

This post explains for the transistor.

The Part Number is A1972, 2SA1972.

The package is TO-92 Type

The function of this semiconductor is 400V, PNP Transistor.

Manufacturer: Toshiba Semiconductor

Preview images :A1972 pinout datasheet


A1972 is 400V, 0.5A, Silicon PNP Triple Diffused Type Transistor. A PNP transistor is a type of bipolar junction transistor (BJT) with a different structure and polarity compared to an NPN transistor.


1. Polarity: In a PNP transistor, the majority charge carriers are holes, which flow from the emitter to the collector. The emitter is negative relative to the base, and the collector is positive relative to the base.

2. Current flow: When a small current is applied to the base terminal, it allows a much larger current to flow from the emitter to the collector. This is called amplification or gain, and it makes the PNP transistor useful as an electronic switch or amplifier.

3. Voltage levels: The voltage levels in a PNP transistor are opposite to those in an NPN transistor. In a NPN transistor, the base-emitter junction is forward-biased and the collector-base junction is reverse-biased.

4. Biasing: PNP transistors are biased in the opposite direction to NPN transistors. To turn on a PNP transistor, the base must be more negative than the emitter, and to turn it off, the base must be more positive than the emitter.


A1972 pdf transistor

Absolute maximum ratings ( Ta=25°C )

1. Collector to Base Voltage: Vcbo = – 400 V

2. Collector to Emitter Voltage: Vceo = – 400 V

3. Emitter to Base Voltage: Vebo = – 7 V

4. Collector Current: Ic = – 0.5 A

5. Collector Dissipation : Pc = 900 mW

6. Junction Temperature: Tj = 150°C

7. Storage Temperature: Tsg = -55 ~ +150°C


A1972 PDF Datasheet