SD1477

Overview

The SD1477 is a 12.5 V Class C epitaxial silicon NPN planar transistor designed primarily for VHF FM communications. It utilizes a diffused emitter structure and operates with a collector-emitter breakdown voltage of 18V. The device is housed in an M111 surface mount package, suitable for mobile applications requiring RF power bipolar transistor performance.

Feature Summary

• Epitaxial silicon NPN planar construction optimized for high-frequency operation
• Diffused emitter technology ensuring stable RF power performance
• Surface mount M111 package design facilitating automated assembly

Applications

• VHF FM communications systems
• Mobile radio transmitters
• RF power amplification stages

Procurement Notes

Verify the obsolete status and availability through authorized distributors before procurement. Confirm that the M111 package matches your PCB footprint requirements. Ensure compatibility with existing VHF circuit designs due to the specific 12.5 V Class C operational characteristics defined by STMicroelectronics.

Selection Notes

Select this component for VHF applications requiring a robust NPN RF power solution. The 18V breakdown voltage provides necessary headroom for 12.5 V systems. Consider the surface mount M111 package for space-constrained mobile designs where thermal management and RF stability are critical for Class C amplifier efficiency.

Part Context

This part belongs to STMicroelectronics' RF power bipolar transistor series targeting VHF mobile applications. It represents a specialized discrete semiconductor component engineered for frequency modulation transmission environments, distinct from general-purpose switching transistors or low-noise amplifiers.

Replacement Considerations

The datasheet indicates the SD1477 is currently obsolete. Engineers should consult official replacement guides or contact STMicroelectronics directly for verified substitute part numbers compatible with the M111 package and VHF specifications.