The BD379 is a silicon NPN epitaxial planar transistor designed for use in a variety of amplifier and switching applications. Manufactured by Fairchild/ON Semiconductor, this transistor is known for its robust performance characteristics and reliability in standard circuit designs. While now categorized as END-OF-LIFE, it was commonly used in audio amplifiers, power supplies, and general-purpose switching circuits.

Applications

• Audio amplifier stages (pre-amplifiers and output stages)
• Switching regulators in power supplies
• General-purpose switching circuits
• Driver stages for higher-power transistors
• Linear amplifiers

Features

• High Collector-Emitter Breakdown Voltage (VCEO)
• High Collector Current (IC) capability
• Low Collector-Emitter Saturation Voltage (VCE(sat))
• Fast Switching Speed
• Epitaxial planar construction for improved reliability

Benefits

• Provides stable and reliable amplification in audio circuits.
• Enables efficient switching in power supply designs, minimizing power loss.
• Offers versatile performance for a wide range of general-purpose applications.
• Reduces power dissipation in switching applications due to low saturation voltage.
• Contributes to robust circuit design due to its high breakdown voltage and current capabilities.

Additional Details

The BD379's technical specifications include a Collector-Emitter Breakdown Voltage (VCEO) typically around 60V, a Collector Current (IC) of up to 1A, and a Power Dissipation (PD) of around 8W. Its operating temperature range is typically from -65°C to +150°C. It comes in a TO-126 package. The DC Current Gain (hFE) varies depending on the collector current but is generally in the range of 40 to 250. While it is now an END-OF-LIFE product, understanding its specifications is helpful in finding appropriate replacement components for existing designs.