BLF278,112

Overview

The BLF278,112 is a VHF push-pull power MOS transistor manufactured by Ampleon USA Inc. It is a dual silicon N-channel enhancement mode vertical D-MOS device housed in an SOT262A1 balanced flange package with two ceramic caps and a mounting flange for common source connection. The component operates at a drain-source voltage of 50 V with a breakdown voltage of 125 V. In Class-B operation at 108 MHz, it delivers 300 W output power with greater than 20 dB gain and over 60% efficiency. At 225 MHz in Class-AB mode, it provides 250 W output power with typical 16 dB gain and 55% efficiency.

Feature Summary

• Dual push-pull configuration with a common source connection via the mounting flange.
• Gold metallization structure designed to ensure excellent reliability.
• Capable of withstanding load mismatches corresponding to VSWR = 7:1 through all phases.
• Features good thermal stability and easy power control characteristics.

Applications

• Broadcast transmitters in the VHF frequency range.

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm package type and tape/reel specifications. Confirm RoHS compliance status as manufacturing processes may evolve. Check for Customer Product/Process Change Notifications (CPCN) regarding any design updates or material changes since the original datasheet release date.

Selection Notes

Select this component for VHF applications requiring high power gain and ruggedness. Ensure the design accommodates the SOT262A1 flange package dimensions and mounting requirements. Verify that the thermal management system can maintain junction temperatures within the specified limits during continuous wave operation.

Part Context

This device belongs to the Ampleon VHF power transistor portfolio, originally developed under Philips Semiconductors. It serves as a specialized solution for broadcast transmitter stages where high linearity and power density are required in the Very High Frequency band.

Replacement Considerations

Consult official substitution lists for equivalent devices. No public confirmed substitute part numbers are available in the provided documentation.

FAQ

What is the maximum drain-source voltage rating?

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

How does the device handle load mismatches?

The BLF278 can withstand a load mismatch corresponding to a Voltage Standing Wave Ratio (VSWR) of 7:1 through all phases under specified operating conditions.

What is the recommended gate resistance per section?

For Class-B operation at 108 MHz, the recommended gate resistance (RGS) is 4 Ω per section.