BLF177CR,112

Overview

The BLF177CR,112 is an HF/VHF power MOS transistor manufactured by Ampleon USA Inc. It is a silicon N-channel enhancement mode vertical D-MOS device housed in a flanged SOT121B package with a ceramic cap. The component features a drain-source voltage rating of 125 V and a total power dissipation of 220 W at 25 °C mounting base temperature. In class-AB operation at 28 MHz with 50 V supply, it delivers up to 150 W PEP output with over 20 dB gain. Class-B CW performance at 108 MHz yields 150 W output with typical 19 dB gain and 70% efficiency.

Feature Summary

• High power gain capability across HF/VHF bands
• Low intermodulation distortion for signal fidelity
• Robust thermal stability under varying load conditions
• Capable of withstanding full load mismatch scenarios

Applications

• Industrial applications in the HF/VHF frequency range
• Military applications requiring high reliability in HF/VHF bands
• SSB amplification in common source class-AB configurations
• CW amplification in common source class-B configurations

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current product data sheet to confirm exact pinning and marking code availability. Ensure that handling procedures account for the beryllium oxide content within the ceramic cap, adhering to local chemical waste disposal regulations to prevent damage to the internal BeO disc during installation or maintenance.

Selection Notes

Select this component for designs operating within the HF/VHF spectrum where high power gain and ruggedness are required. Consider the SOT121B flanged package for effective heat sinking via the mounting base. Evaluate the gate-source voltage threshold groups (A-Z) if matched pair applications are necessary to ensure balanced performance between parallel devices.

Part Context

The BLF177 series represents a line of silicon N-channel enhancement mode vertical D-MOS transistors designed specifically for high-power RF applications. Manufactured originally by Philips Semiconductors and later NXP Semiconductors, these devices utilize a flanged ceramic package to facilitate efficient thermal management. The BLF177CR variant falls within this family, optimized for industrial and military use cases demanding reliable performance in the HF and VHF bands.

Replacement Considerations

Consult official substitution lists from Ampleon or NXP Semiconductors for verified equivalents. Generic replacements may not match the specific thermal resistance or impedance characteristics required for HF/VHF power amplifier stages.

FAQ

What is the maximum drain-source voltage rating for the BLF177?

The absolute maximum drain-source voltage (VDS) rating is 125 V.

How does the BLF177 handle load mismatches?

The device is designed to withstand full load mismatch, capable of operating with a VSWR of 50 through all phases at rated output power.

What packaging type is used for the BLF177?

It is encapsulated in a 4-lead, SOT121B flanged package featuring a ceramic cap, with all leads isolated from the flange.