STMICROELECTRONICS BD437 NPN Power Transistor, TO-126

The STMICROELECTRONICS BD437 is a robust NPN silicon complementary epitaxial-base power transistor, housed in a standard TO-126 package. Designed for reliability, it is engineered for medium-power linear and switching applications, offering a dependable solution for controlling current in a variety of electronic circuits.

This transistor supports a maximum collector-emitter voltage of 45V and a continuous collector current of 4A, with a power dissipation rating of 36W. Its high DC current gain (hFE), with a minimum of 140, ensures efficient signal amplification. The through-hole mounting and three-pin configuration make it straightforward to integrate into printed circuit boards (PCBs) for secure and stable connections.

The component is well-suited for industrial and power management systems, where consistent performance under load is critical. Its complementary PNP type is the BD438, allowing for flexible circuit design in push-pull and other complementary configurations. With an operating temperature maximum of 150°C, it is built to withstand demanding environments.

Key Specifications

• Transistor Polarity: NPN
• Collector-Emitter Voltage (Max): 45V
• Continuous Collector Current: 4A
• Power Dissipation: 36W
• Case Style: TO-126
• Mounting Type: Through Hole
• Number of Pins: 3
• Transition Frequency: 3MHz
• DC Current Gain (hFE Min): 140
• Maximum Operating Temperature: 150°C

This transistor is a fundamental component for designers and technicians looking for a proven, medium-power switching and amplification device from a leading semiconductor manufacturer.