2N1909

Overview

The Powerex Inc. 2N1909 is a silicon planar epitaxial base power transistor designed for high-voltage, high-current applications. It features a hermetically sealed TO-3 metal case construction suitable for robust industrial environments. Key electrical parameters include a collector-emitter voltage (VCEO) of 60 V and a collector-base voltage (VCBO) of 80 V. The device supports a continuous collector current (IC) of 15 A and a peak collector current (ICM) of 30 A. Total power dissipation (PTOT) is rated at 125 W when mounted on an insulated heatsink at 25°C ambient temperature. The component operates within a junction temperature range of -65°C to +200°C.

Feature Summary

• Hermetically sealed TO-3 metal package ensures reliability in harsh environments
• Planar epitaxial base structure provides stable high-voltage performance
• High thermal stability with extended junction temperature capability up to 200°C

Applications

• Linear voltage regulators
• Power amplifiers
• Motor control circuits

Procurement Notes

Verify the specific manufacturer lot code and date code against the original datasheet revision history to ensure compliance with historical specifications. Confirm that the TO-3 package pinout matches the intended circuit design, as legacy components may have variations in lead configuration or insulation requirements compared to modern equivalents.

Selection Notes

Select this component for designs requiring discrete high-power NPN transistors with proven reliability. Ensure the thermal management system can handle the 125 W dissipation rating under worst-case operating conditions. Verify that the drive circuitry can supply sufficient base current to maintain saturation or linear operation at the required 15 A collector current level without exceeding maximum ratings.

Part Context

The 2N1909 belongs to the family of general-purpose high-power silicon NPN transistors historically manufactured by Powerex Inc. These devices were widely used in industrial power supplies and audio equipment before the prevalence of integrated switching regulators. The part number represents a standard military-style specification compatible with various OEM designs from the late 20th century.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Designers should consult official cross-reference lists from Powerex or authorized distributors for equivalent TO-3 NPN power transistors with matching voltage and current ratings.