NXP Semiconductors MRF1K50N-88MHZ

Overview

MRF1K50N-88MHZ from NXP Semiconductors is a high-ruggedness, 50 V, 1500 W CW RF power LDMOS transistor optimized for broadband operation from 87.5–108 MHz. It delivers 1421 W output power, 23.1 dB power gain, and 83.2% drain efficiency at 98 MHz under CW conditions with 50 Vdc supply and 200 mA quiescent current per side. It serves as the active RF power stage in high-VSWR industrial heating and broadcast amplifiers.

For engineers reviewing the MRF1K50N-88MHZ datasheet, MRF1K50N-88MHZ pinout, MRF1K50N-88MHZ application, or MRF1K50N-88MHZ equivalent, key selection criteria include its 133 Vds breakdown rating, 0.068 °C/W thermal resistance (junction-to-case), 65:1 load mismatch tolerance at 230 MHz, and dual-gate/dual-drain configuration enabling push-pull or single-ended use in VHF broadcast and ISM systems.

Technical Context

This device is a lateral N-channel enhancement-mode LDMOS transistor with integrated ESD protection (HBM Class 2, CDM Class C3) and rated for junction temperatures up to +225°C. Its unmatched input/output impedance design supports stable broadband operation from 1.8–500 MHz without external harmonic tuning in reference circuits.

It operates with gate threshold voltage of 1.7–2.7 Vdc and gate quiescent voltage of 1.9–2.9 Vdc at 50 Vdd and 100 mA total quiescent current. The dual-gate/dual-drain structure allows balanced push-pull configurations while maintaining independent control of each half of the die.

Key Specifications

Pinout & Package

The MRF1K50N-88MHZ uses the OM-1230-4L plastic overmolded package with exposed source on the backside. Thermal performance relies on direct metal-to-heatsink contact via the source terminal.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RF power transistor applications.

Compared with MRF1K50GN, the MRF1K50N-88MHZ offers identical RF performance but requires manual lead forming and through-hole heatsink attachment, whereas MRFE6VS25N is functionally a driver-not a power-stage alternative-making it unsuitable for direct substitution in final amplifier positions.

Availability

MRF1K50N-88MHZ is available at Aetrix Electronics and suitable for FM broadcast transmitters, industrial plasma generators, VHF TV repeaters, and aerospace VOR beacons requiring stable component supply across long-life, high-reliability deployments.

Supply support for MRF1K50N-88MHZ 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 communication infrastructure markets.

The MRF1K50N-88MHZ belongs to NXP's high-ruggedness RF power LDMOS family, engineered specifically for mission-critical broadband amplification in industrial heating, broadcast, and aerospace systems where reliability under extreme VSWR is mandatory.

FAQ

What is the maximum continuous drain current rating for the MRF1K50N-88MHZ?

The MRF1K50N-88MHZ does not specify a maximum continuous drain current in absolute terms; instead, its safe operating area is defined by junction temperature limits (–40°C to +225°C), thermal resistance (0.068 °C/W), and maximum dissipation (2941 W at T_C = 25°C). At 50 Vdc and 1500 W CW output, typical total quiescent current is 200 mA per side, with peak conduction current exceeding 35 A during RF cycles. Designers must verify current density and bond wire integrity using NXP's MTTF calculator and AN1955 thermal methodology.

Can the MRF1K50N-88MHZ operate safely at frequencies outside the 87.5–108 MHz band?

Yes - the MRF1K50N-88MHZ is characterized from 1.8–500 MHz and validated for use at 230 MHz (pulse mode) and across HF/VHF/UHF bands. Its unmatched input/output design enables broadband operation without harmonic traps. However, output power, gain, and efficiency vary by frequency: at 230 MHz it delivers 1500 W peak (75.1% η_D), while at 1.8 MHz it supports lower-power linear applications. Always consult Tables 5 and 8–10 and Figures 7–17 for frequency-specific performance data before finalizing matching networks.

What is the recommended gate bias voltage for Class AB operation of the MRF1K50N-88MHZ?

The MRF1K50N-88MHZ specifies a gate quiescent voltage (V_GS(Q)) of 1.9–2.9 Vdc at 50 Vdd and 100 mA total quiescent current (50 mA per side), which corresponds to Class AB biasing. For optimal linearity and efficiency in FM broadcast applications, NXP recommends setting V_GS(Q) to ~2.4 Vdc using precision bias networks. Gate threshold voltage is 1.7–2.7 Vdc, so bias must remain above this range to ensure full enhancement while avoiding excessive I_DSS leakage. Refer to Figure 3 for V_GS(Q) vs. case temperature compensation.

Does the MRF1K50N-88MHZ require external ESD protection in PCB layout?

No - the MRF1K50N-88MHZ integrates on-die ESD protection rated to Class 2 HBM (2500 V) and Class C3 CDM (2000 V), eliminating the need for external TVS diodes on gate lines in standard handling environments. However, NXP still recommends standard RF PCB ESD controls: short gate traces, grounded guard rings, and avoidance of floating conductors near gate pins. The device's extended negative gate-source voltage range (–6.0 Vdc) further enhances robustness during Class C switching transitions.

How is thermal management implemented for the MRF1K50N-88MHZ in high-power applications?

Thermal management for the MRF1K50N-88MHZ relies on direct mounting of its exposed source pad to a copper heatsink using thermally conductive interface material (e.g., thermal grease or solder per AN1907). With R_θJC = 0.068 °C/W, a 1500 W CW application generates only ~102°C temperature rise from case to junction - well within the +225°C limit. Heatsink design must maintain case temperature ≤80°C (CW) or ≤75°C (pulse), and airflow or liquid cooling must be sized accordingly. NXP provides heatsink drawings and thermal simulation models (.s2p, MTTF calculator) on nxp.com/RF.