The BC640 is a PNP high current silicon transistor and it is commonly used in switching and amplifier circuits. It belongs to the BC636–BC640 family and is is designed to handle moderate current levels with good gain characteristics. Due to its compact TO-92 package, it is used in low power and medium power electronic projects. So, in this article describes the Pinout, Specifications and Equivalent.
BC640 Transistor Overview
- Transistor Type: PNP Transistor
- Material: Silicon
- Package: TO-92
- Maximum Collector Current: 500 mA
- Collector – Emitter Voltage: -80 V
BC640 Transistor Pinout
To check the pinout of transistor, you just hold the transistors flat side facing you and pins are pointing downward and count the pin from left to right, then the corresponding pinout is given below,
Pinout configuration
| Pin Number | Pin Name |
|---|---|
| 1 | Emitter (E) |
| 2 | Collector (C) |
| 3 | Base (B) |
Features and Specifications
- Collector-Emitter Voltage VCEO: −80 V
- Collector-Base Voltage VCBO:−80 V
- Emitter-Base Voltage VEBO:−5 V
- Collector Current (Continuous) IC:−500 mA
- Power Dissipation PD: 625 mW
- Junction Temperature T: −55°C to +150°C
Equivalent Transistor for Replacement
- BC638
- BC636
- 2N2907
- 2N4403
- S8550
⚠ Always check specifications and pinout configurations before replacing the transistor.
Applications
- Audio amplifier stages.
- Relay and motor drivers.
- Signal switching circuits.
- Power management circuits.
- General purpose PNP switching circuit.
Frequently Asked Questions (FAQ)
Yes, the BC640 works very well as a PNP switching transistor in low-side and high-side switching applications.
BC638, BC636, 2N2907, 2N4403, and S8550 provided voltage and current ratings are compatible.
