MRF275G

Overview

The MRF275G is an N-channel enhancement mode RF MOSFET designed for wideband large-signal output and driver stages from 100 to 500 MHz. It operates at 28 Vdc with a guaranteed minimum output power of 150 W and power gain of 10 dB at 500 MHz. The device features low capacitance values, including Ciss of 135 pF, Coss of 140 pF, and Crss of 17 pF. It is tested for load mismatch with VSWR up to 30:1.

Feature Summary

• N-channel enhancement mode construction
• Immunity from thermal runaway
• Ability to withstand severely mismatched loads without damage
• Power output controllable via DC gate voltage

Applications

• Wideband large-signal output stages
• Driver stages
• HF, VHF, and UHF power amplifier applications

Procurement Notes

Verify the specific datasheet revision (e.g., Rev. V1) against your design requirements before procurement. Confirm that the package style matches CASE 375-04, Style 2. Ensure handling procedures strictly follow antistatic protocols, as the device lacks internal gate protection and requires careful management of gate-to-source impedance to prevent oxide layer damage.

Selection Notes

Select this component for applications requiring high gain and simple bias systems within the 100–500 MHz range. The device supports linear amplification where quiescent drain current can be optimized. Consider its relative immunity to thermal runaway and the ability to vary power output over a wide range using low-power DC control signals for modulation or AGC designs.

Part Context

The MRF275G belongs to the MACOM RF MOSFET line, characterized by vertical structure and planar design. These transistors are engineered for industrial and commercial power amplifier applications, offering advantages such as low noise and simplified automatic voltage control (AVC) and automatic level control (ALC) circuitry compared to other RF transistor technologies.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.

FAQ

Does the MRF275G have internal gate protection?

No, the device does not have an internal monolithic Zener diode from gate-to-source. External Zener diodes are recommended if gate protection is required.

What is the suggested minimum quiescent drain current (IDQ)?

The MRF275G was characterized at IDQ = 100 mA per side, which is the suggested minimum value for optimal performance.

How is the power output controlled?

Power output may be controlled from its rated value down to zero (negative gain) by varying the DC gate voltage, facilitating manual gain control and modulation systems.