Texas Instruments LMG3422R050RQZT

Overview

LMG3422R050RQZT from Texas Instruments is a 600V, 50mΩ GaN-on-Si power FET with integrated gate driver, cycle-by-cycle overcurrent protection (<100ns response), 20–150V/ns adjustable slew rate, and digital temperature PWM reporting. It operates from 7.5V–18V supply and withstands 720V surge during hard-switching - deployed in high-density server PSUs and telecom rectifiers.

For engineers reviewing the LMG3422R050RQZT datasheet, LMG3422R050RQZT pinout, LMG3422R050RQZT application, or LMG3422R050RQZT equivalent, key selection criteria include verified 50mΩ R_DS(on) at 25°C, confirmed 54-pin RQZ (VQFN) package with thermal pad, absence of ZVD/ZCD features (distinguishing it from LMG3426R050/LMG3427R050), and direct-drive IN interface requiring no external level-shifting.

Technical Context

The LMG3422R050RQZT integrates a silicon-based gate driver with precision bias regulation, enabling clean 150V/ns switching without external gate resistors. Its depletion-mode GaN FET uses internal buck-boost converter (VNEG/BBSW) to generate negative turn-off voltage, eliminating need for external negative rail.

Protection architecture includes independent OCP/SCP latching with <100ns detection latency, self-monitoring UVLO on VDD and VNEG, and dual-stage thermal shutdown (175°C GaN junction, 185°C driver). Unlike LMG3426R050/LMG3427R050, it lacks zero-voltage or zero-current detection outputs - confirmed by device information table and pin function mapping.

Key Specifications

Pinout & Package

The LMG3422R050RQZT uses a 54-pin RQZ (VQFN) package with 12.0 mm × 12.0 mm footprint and exposed thermal pad connected internally to SOURCE, GND, and NC2 pins. Thermal pad must be soldered to PCB for electrical continuity and thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar GaN FET applications.

Compared with LMG3426R050RQZT, LMG3422R050RQZT offers identical power stage performance but omits ZVD functionality - reducing cost and complexity in hard-switched topologies. Versus UCC27611DR, LMG3422R050RQZT provides full protection integration and thermal telemetry, eliminating four external components and simplifying safety certification.

Availability

LMG3422R050RQZT is available at Aetrix Electronics and suitable for server PSU primary switches, telecom rectifier high-side switches, and solar inverter DC link stages requiring stable component supply, long-term lifecycle support, and JEDEC JEP180-qualified hard-switching reliability.

Supply support for LMG3422R050RQZT 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

Texas Instruments is a global semiconductor leader focused on analog, embedded processing, and power management technologies, serving industrial, automotive, and communications markets.

The LMG342xR050 product line delivers integrated GaN power stages for high-density, high-efficiency switch-mode power conversion - designed specifically to replace discrete Si MOSFET + driver solutions in 600V-class SMPS.

FAQ

What is the maximum continuous drain current rating for LMG3422R050RQZT?

The LMG3422R050RQZT supports 44 A RMS drain current under recommended operating conditions. This rating assumes proper PCB thermal design with the exposed thermal pad fully soldered to a multi-layer copper plane. Peak pulsed current is internally limited to 96 A for pulses under 10 µs, but sustained operation above 44 A RMS risks thermal runaway due to junction temperature exceeding 150°C.

Does LMG3422R050RQZT include zero-voltage or zero-current detection features?

No, LMG3422R050RQZT does not include zero-voltage detection (ZVD) or zero-current detection (ZCD) features. These functions are exclusive to LMG3426R050RQZT (ZVD) and LMG3427R050RQZT (ZCD), as confirmed in the Device Information table and pin function descriptions. LMG3422R050RQZT's OC pin provides overcurrent fault signaling only - no soft-switching assist outputs.

How is temperature reported by LMG3422R050RQZT, and what is its accuracy?

LMG3422R050RQZT reports junction temperature via a 9 kHz PWM output on the TEMP pin, where duty cycle linearly encodes temperature: 0.3–6% at 25°C, 36–44% at 85°C, 59–70% at 125°C, and 82% at 150°C. Accuracy is ±5°C across –40°C to 150°C, validated per TI's characterization data. No external calibration is required - the signal is directly readable by any microcontroller with PWM capture or simple RC-filtered ADC.

What is the purpose of the VNEG and BBSW pins on LMG3422R050RQZT?

VNEG and BBSW implement an internal buck-boost converter that generates a –14 V negative gate bias for reliable depletion-mode GaN FET turn-off. VNEG is the negative output node requiring a 2.2 µF bypass capacitor to GND; BBSW is the internal switch node connecting to an external 3–10 µH inductor. This eliminates need for external negative supplies while ensuring robust gate control under high dV/dt conditions.

Can LMG3422R050RQZT be used in parallel configurations, and what layout considerations apply?

Yes, LMG3422R050RQZT supports paralleling for higher current capacity, but requires matched gate loop inductance and symmetrical thermal paths. TI recommends identical RDRV resistor values per device, Kelvin source connections, and individual 2.2 µF VNEG bypass capacitors. The 54-pin RQZ package's distributed SOURCE pins (18–40) and thermal pad facilitate low-inductance, low-impedance paralleling - critical to avoid current imbalance above 100 A total RMS.