This post explains for the transistor 2SB1274.
The Part Number is B1274.
The function of this semiconductor is PNP Transistor.
The pacakge is TO-220ML Type
Manufacturer: Sanyo Semicon Device
Preview images :
B1274 is -60V, -3A, PNP Epitaxial Planar Silicon Transistor. A PNP transistor is a type of bipolar junction transistor (BJT) with a different structure and polarity compared to an NPN transistor.
Characteristics of PNP transistors:
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.
Absolute maximum ratings ( Ta=25°C )
1. Collector to Base Voltage: Vcbo = – 60 V
2. Collector to Emitter Voltage: Vceo = – 60 V
3. Emitter to Base Voltage: Vebo = – 6 V
4. Collector Current: Ic = – 3 A
5. Collector Dissipation : Pc = 2 W
6. Junction Temperature: Tj = 150°C
7. Storage Temperature: Tsg = -55 ~ +150°C
• Wide ASO (Adoption of MBIT process).
• Low saturation voltage.
• High reliability.
• High breakdown voltage.
• Micaless package facilitating mounting.