SD1446

Overview

The SD1446 is a 12.5 V Class C epitaxial silicon NPN planar transistor designed primarily for land mobile transmitter applications. This high-power device features a maximum DC collector current of 12 A and a power dissipation rating of 183 W. It operates within the HF/VHF frequency range, specifically up to 50 MHz. The component utilizes emitter ballasting to ensure stability and withstand high VSWR under operating conditions.

Feature Summary

• Epitaxial silicon NPN planar construction optimized for RF applications
• Integrated emitter ballasting for enhanced operational stability
• High tolerance for standing wave ratio (VSWR) stress

Applications

• Land mobile transmitter circuits
• HF/VHF communication systems
• Class C RF power amplification

Procurement Notes

Verify the specific package marking and date code against official STMicroelectronics documentation to confirm authenticity. Ensure the received components match the SD1446 designation exactly, as variations in suffixes may indicate different thermal or electrical characteristics not covered by this primary specification sheet.

Selection Notes

Select this component when designing land mobile transmitters requiring robust performance at 12.5 V with significant current handling capabilities. The integrated emitter ballasting makes it suitable for environments prone to impedance mismatches, ensuring reliable operation where standard transistors might fail due to VSWR-induced instability.

Part Context

This device belongs to the STMicroelectronics RF Bipolar Transistor family, targeting professional communication equipment. It is distinct from general-purpose switching transistors, focusing instead on linear and Class C RF power amplification tasks within the HF and VHF bands for mobile radio infrastructure.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Cross-referencing requires consulting official STMicroelectronics replacement guides or engineering change notices to ensure compatibility with voltage, current, and thermal requirements.