MX0912B251Y,114

Overview

The MX0912B251Y is an NPN silicon planar epitaxial microwave power transistor housed in a SOT439A metal ceramic flange package. Designed for common base class C operation, it delivers over 235 W of output power with greater than 7 dB gain and over 42% collector efficiency across the 0.960 to 1.215 GHz frequency range. The device features an interdigitated structure with diffused emitter ballasting resistors for excellent current sharing and high VSWR tolerance. It operates at a 50 V supply voltage with a peak total power dissipation of 690 W under specified pulse conditions.

Feature Summary

• Interdigitated structure with high emitter efficiency
• Diffused emitter ballasting resistors for superior current sharing and VSWR withstand capability
• Gold metallization ensuring stable characteristics and extended lifetime
• Multicell geometry balancing dissipated power with low thermal resistance

Applications

• Common base class C broadband pulse power amplifiers
• TACAN (Tactical Air Navigation) systems operating between 960 and 1215 MHz

Procurement Notes

Verify component authenticity by checking datasheet revision dates against the original Philips Semiconductors publication from February 1997. Confirm that the physical package matches the SOT439A outline dimensions and pin configuration. Ensure handling procedures account for the presence of beryllium oxide within the ceramic substrate, requiring specific disposal protocols as chemical waste rather than general refuse.

Selection Notes

Select this component when designing broadband pulse amplifiers requiring high power density in the L-band frequency range. The device requires a common base configuration and must be mounted on a heatsink capable of maintaining the mounting base temperature within limits defined by the derating curve. Verify that the application circuit can provide the necessary input and output impedances shown in the Smith chart data for optimal performance.

Part Context

This part was originally manufactured by Philips Semiconductors, which later became NXP Semiconductors. The MX0912B251Y belongs to a family of NPN microwave power transistors designed for robust RF applications. It utilizes a metal ceramic construction typical of high-power microwave devices from the late 1990s, emphasizing reliability through gold metallization and specialized thermal management structures.

Replacement Considerations

No direct public substitute part numbers are documented in the provided source material.