BD249C NPN Transistor 100V 25A TO-218
The BD249C is a silicon NPN power bipolar junction transistor (BJT) designed for high-current and high-power electronic applications. It provides reliable switching and amplification capabilities, making it suitable for circuits that require controlling substantial electrical loads or amplifying signals at higher power levels.
Featuring a TO-3P power package, the BD249C is designed for through-hole mounting and heatsink installation to help dissipate heat during operation. It is commonly used in audio power amplifiers, DC motor controllers, power supply circuits, voltage regulators, and industrial electronic equipment where high current handling and power amplification are required.
Features:
- High-power NPN bipolar transistor.
- Designed for power amplification and switching.
- High-current handling capability.
- Suitable for linear and switching applications.
- Through-hole mounting package.
- Compatible with heatsink installation.
- Silicon semiconductor construction.
Specifications:
| Parameter | Value |
|---|---|
| Part Number | BD249C |
| Transistor Type | NPN Bipolar Power Transistor |
| Polarity | NPN |
| Semiconductor Material | Silicon |
| Collector-Emitter Voltage (VCEO) | 100V |
| Collector-Base Voltage (VCBO) | 115V |
| Emitter-Base Voltage (VEBO) | 5V |
| Continuous Collector Current (IC) | 25A |
| Peak Collector Current (ICM) | 40A |
| Continuous Base Current (IB) | 5A |
| Maximum Power Dissipation | 125W |
| DC Current Gain (hFE) | 25 minimum at 1.5A |
| Transition Frequency | 3MHz |
| Junction Temperature | -65°C to +150°C |
| Package | TO-218 |
| Number of Pins | 3 |
| Mounting Type | Through-Hole |

Pinout

| Pin Number | Pin Name | Function |
|---|---|---|
| 1 | Base (B) | Controls transistor operation |
| 2 | Collector (C) | Main current connection |
| 3 | Emitter (E) | Current output / return |
Applications:
- Audio power amplifier circuits.
- DC motor control systems.
- High-current switching circuits.
- Regulated power supplies.
- Voltage regulator circuits.
- Industrial control equipment.
- Power management circuits.
- General-purpose power amplification.
Package Includes:
- 1 × BD249C NPN Transistor 100V 25A TO-218.





