BLF647,112

Overview

The BLF647 is a silicon N-channel enhancement mode lateral D-MOS push-pull transistor designed for UHF broadband applications. It operates in the HF to 800 MHz range with a drain-source voltage rating of 65 V and a total power dissipation of 290 W. The device delivers 120 W output power at 600 MHz and 150 W at 800 MHz, both exceeding 14.5 dB gain. Packaged in a SOT540A flanged ceramic housing, it features an internal input damping network for stability and a source connection on the underside to minimize common-mode inductance.

Feature Summary

• Push-pull configuration utilizing dual gates and drains within a single package
• Internal input damping circuitry ensures excellent stability across the entire frequency range
• Underside source connection eliminates the need for DC isolators and reduces common mode inductance
• High ruggedness capable of withstanding severe load mismatches

Applications

• Communication transmitter applications in the HF to 800 MHz frequency range
• Broadband RF power amplification in Class-AB operation
• Pulsed power applications requiring high linearity

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current catalog to confirm availability and packaging format. Ensure that the procurement documentation matches the exact part number designation to avoid discrepancies in technical specifications or pin configurations during integration.

Selection Notes

Select this component for designs requiring high power density and wide bandwidth coverage up to 800 MHz. The thermal resistance from junction to mounting base is 0.6 K/W; ensure the heatsink interface maintains a thermal resistance below 0.2 K/W to sustain maximum power dissipation ratings effectively.

Part Context

Originally developed by Philips Semiconductors, this product was transferred to Ampleon following the spin-off of the RF Power division in December 2015. The datasheet retains historical Philips references while officially adopting the Ampleon trade name for all subsequent documentation and contact details.

Replacement Considerations

Consult official substitution lists for equivalent LDMOS transistors with matching power levels and frequency ranges. Verify that any alternative device supports the required SOT540A footprint or requires mechanical adaptation for the flange-mounted configuration.

FAQ

What is the maximum load mismatch the BLF647 can withstand?

The device can withstand a load mismatch corresponding to a VSWR of 10:1 through all phases under rated load power conditions.

How is the source terminal connected in the SOT540A package?

The common source is connected directly to the mounting flange, which facilitates direct grounding and reduces common-mode inductance.

What is the typical power gain at 600 MHz?

At 600 MHz with a 28 V supply, the power gain exceeds 14.5 dB in continuous wave Class-AB operation.