BC640 PNP Transistor Pinout Datasheet

Introduction

The BC640 is a PNP silicon bipolar junction transistor (BJT) designed for medium power amplification and switching applications. It is part of the BC63x family of transistors, which includes the BC636, BC638, and BC640, all popular in the electronics industry for their reliability and versatility. The BC640 offers a high collector-emitter voltage rating of up to 80V and a collector current of 1A, making it suitable for audio amplifier output stages, signal drivers, and control circuits that demand efficient performance and durability.

This transistor is commonly used in push-pull amplifier circuits, where it works as a complementary device with the BC639 NPN transistor. Its wide frequency response, low saturation voltage, and stable gain characteristics make it an excellent choice for low- and medium-frequency amplification. In audio and general-purpose analog circuits, the BC640 ensures clear sound reproduction and reliable current control under varying load conditions.

BC640 PNP High Current Transistor

The BC640 comes in a TO-92 or TO-126 package, offering compactness for PCB mounting while maintaining sufficient heat dissipation capacity. Its thermal stability, good linearity, and robust electrical performance make it a reliable option in industrial, consumer, and automotive electronics where consistent transistor behavior is essential.

BC640 Pinout

Pin Configuration

Pin#	Pin Name	Pin Description
1	Emitter (E)	Current flows out of the transistor; typically connected to the negative supply rail.
2	Base (B)	Controls the transistor’s operation; a small current here controls a larger current between collector and emitter.
3	Collector (C)	Output terminal where main current flows when the transistor is active.

BC640 Pin Configuration

Key Features

PNP silicon transistor for medium power amplification
High collector-emitter voltage (up to 80V)
Maximum collector current of 1A
Excellent linearity for audio and signal amplification
Low collector-emitter saturation voltage
High DC current gain with good thermal stability
Suitable for complementary amplifier stages
Reliable operation with wide frequency response

Characteristics

Transistor Type: PNP
Collector-Emitter Voltage (Vceo): 80V
Collector-Base Voltage (Vcbo): 80V
Emitter-Base Voltage (Vebo): 5V
Maximum Collector Current (Ic): 1A
DC Current Gain (hFE): 40 to 160 typical
Power Dissipation (Ptot): 1.25W (for TO-126 package)
Transition Frequency (fT): 50MHz typical
Collector-Emitter Saturation Voltage (Vce(sat)): 0.3V typical
Operating and Storage Temperature Range: -65°C to +150°C
Package Type: TO-92 / TO-126

Comparison of BC636, BC638, BC640

BC636 supports a collector-emitter voltage of 45V and is best for low-voltage amplifier and general-purpose switching applications.
BC638 offers a 60V collector-emitter rating and better power dissipation, ideal for medium-voltage amplifier and driver circuits.
BC640 provides the highest voltage rating of 80V, making it the most robust in the series for high-voltage amplification, audio outputs, and industrial control circuits.
In summary, BC636 is optimized for low-voltage circuits, BC638 for balanced medium-power use, and BC640 for high-voltage, durable performance in advanced applications.

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Key Applications of BC640 Transistor

Audio amplifier driver and output stages
Low- and medium-frequency amplifier circuits
Signal and voltage amplification in analog systems
Switching and control circuits in power management
Push-pull and complementary output configurations
Consumer and industrial electronic products

NPN Complementary Transistor

The BC640 has the BC639 as its NPN complementary transistor. These two devices are often paired in push-pull amplifier designs and symmetrical audio output circuits, ensuring efficient amplification and smooth waveform reproduction with minimal distortion.

Equivalent of BC640 PNP Transistor

BC636, BC638, 2N2907, BD136, BC327, 2SA1015, 2SA733
These transistors can serve as equivalent or alternative replacements depending on circuit requirements for voltage, current, and gain. Always verify pinout and ratings before substitution.

(Pin configuration of some transistors mentioned above may different from BC640).

Datasheet of BC640 PNP Transistor

Click the following Button to download the datasheet of BC640 Transistor :

Download Datasheet

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