NXP Semiconductors MRF101AN-81MHZ

Overview

MRF101AN-81MHZ from NXP Semiconductors is a frequency-optimized reference circuit board built around the MRF101AN 100 W RF power LDMOS transistor, operating at 81.36 MHz under 50 Vdc supply, delivering 130 W CW output with 23.2 dB power gain and 80.8% drain efficiency in a 2.0″×3.0″ FR4 layout for industrial plasma and broadcast amplifier stages.

For engineers reviewing the MRF101AN-81MHZ datasheet, MRF101AN-81MHZ application, MRF101AN-81MHZ pinout, or MRF101AN-81MHZ equivalent, this board provides validated impedance matching (Z_source = 12.0 + j11.0 Ω, Z_load = 11.5 + j3.0 Ω), thermal design (77°C case temp), and ruggedness validation (>65:1 VSWR tolerance) for HF/VHF RF power amplifier development.

Technical Context

The MRF101AN-81MHZ implements a single-ended common-source Class AB amplifier topology using the MRF101AN LDMOS device, biased at 100 mA quiescent drain current with gate voltage set via a 5 V regulator (LP2951ACDMR2G) and trim potentiometer (3224W-1-502E) for precise V_GS(Q) control.

Its matching network employs discrete air-core and chip inductors (L3: 3-turn #18 AWG, L4: 7-turn #18 AWG, L1: 56 nH, L2: 6.6 nH) and high-stability NP0/C0G capacitors (C1–C8: 1000 pF, C2: 200 pF, C3: 100 pF) to transform 50 Ω source/load impedances to the transistor's optimal Z_in and Z_out at 81.36 MHz.

Key Specifications

Availability

MRF101AN-81MHZ is available at Aetrix Electronics and suitable for industrial plasma etching, broadcast transmitter exciter stages, MRI RF power modules, and aerospace telemetry uplinks requiring stable component supply and proven RF performance at 81 MHz.

Supply support for MRF101AN-81MHZ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader specializing in secure connectivity solutions for automotive, industrial, and communications markets, with deep expertise in RF power devices and system-level reference designs.

The MRF101AN-81MHZ belongs to NXP's RF Power LDMOS Reference Circuit family, engineered to accelerate time-to-market for rugged, high-efficiency HF/VHF amplifiers in mission-critical industrial and broadcast applications.

FAQ

What is the MRF101AN-81MHZ used for?

The MRF101AN-81MHZ is a fully assembled 81.36 MHz reference circuit board designed to demonstrate and validate the performance of the MRF101AN RF power transistor in high-power linear amplifier applications. It delivers 130 W CW output with 23.2 dB gain and 80.8% efficiency, targeting industrial plasma systems, broadcast exciters, and medical RF generators where stable, repeatable 81 MHz operation is required.

Does the MRF101AN-81MHZ include the MRF101AN transistor?

Yes, the MRF101AN-81MHZ includes one MRF101AN RF power LDMOS transistor mounted on the board. The MRF101AN is a TO-220-3L packaged device with Gate–Source–Drain pinout (Pin 1: Gate, Pin 2: Source, Pin 3: Drain), and its exposed tab serves as the source terminal and thermal path to the heatsink.

What are the key passive components on the MRF101AN-81MHZ board?

The MRF101AN-81MHZ uses Murata GRM2165C2A102JA01D (1000 pF), GQM2195C2A201GB12D (200 pF), and GQM2195C2E101GB12D (100 pF) NP0/C0G capacitors; ATC 0805WL560JT (56 nH) and GA3093-ALC (6.6 nH) inductors; Fair-Rite 2743019447 RF bead; KOA Speer SG73P2ATTD75R0F (75 Ω) resistor; and ON Semiconductor LP2951ACDMR2G 5 V regulator - all selected for stability and low loss at 81 MHz.

Can the MRF101AN-81MHZ be used outside the 81.36 MHz band?

No - the MRF101AN-81MHZ is a narrowband reference circuit optimized specifically for 81.36 MHz operation. Its matching network (Z_source = 12.0 + j11.0 Ω, Z_load = 11.5 + j3.0 Ω), component values, and layout are not broadband; deviation beyond ±1 MHz significantly degrades gain, efficiency, and VSWR tolerance. For other frequencies, use the corresponding reference circuit (e.g., MRF101AN-50MHZ or MRF101AN-VHF).

Is thermal management provided on the MRF101AN-81MHZ board?

Yes - the MRF101AN-81MHZ board includes a thermally robust design: the MRF101AN's exposed TO-220-3L tab is soldered directly to a large copper pour connected to mounting holes, enabling direct attachment to an external heatsink. Performance data was validated at 77°C case temperature, confirming suitability for forced-air or conduction-cooled systems.