Texas Instruments LMG3526R050RQST

Overview

LMG3526R050 from Texas Instruments is a 650V, 50mΩ GaN-on-Si power FET with monolithically integrated gate driver, cycle-by-cycle overcurrent protection (<100ns response), zero-voltage detection (ZVD), and digital temperature PWM reporting. It operates from 7.5V–18V supply, supports up to 3.6MHz switching, and delivers 15–150V/ns adjustable slew rate for EMI-optimized hard- and soft-switching in high-density PSUs.

For engineers reviewing the LMG3526R050 datasheet, LMG3526R050 pinout, LMG3526R050 application, or LMG3526R050 equivalent, this page provides verified technical context, validated pin functions, confirmed ZVD timing parameters (tDL_ZVD = 15–30ns, tWD_ZVD = 75–140ns), real-world thermal metrics (RθJC(top) = 0.68°C/W), and two rigorously validated alternative GaN FETs with documented functional distinctions.

Technical Context

The LMG3526R050 implements a direct-drive architecture with silicon-based gate driver co-integrated on the same die as the GaN HEMT, eliminating external gate driver loop inductance and enabling 150V/ns turn-on slew rate. Its internal buck-boost converter generates VNEG (–14V) for reliable depletion-mode GaN turn-off, while the RDRV pin sets drive strength via external resistor (0–500kΩ) to tune slew rate across 15–150V/ns.

Zero-voltage detection (ZVD) is implemented as a dedicated push-pull output (Pin 48) that pulses during third-quadrant conduction when VDS crosses zero - with defined timing windows: t3rd_ZVD = 42–56ns at 5A, tDL_ZVD = 15–30ns, and tWD_ZVD = 75–140ns. Fault reporting includes independent OC (overcurrent), FAULT (latched faults), and TEMP (9kHz PWM duty-cycle-encoded temperature).

Key Specifications

Pinout & Package

LMG3526R050 uses a 52-pin, 12mm × 12mm VQFN package (RQS) with exposed thermal pad internally connected to SOURCE and NC2 pins. Electrical and thermal paths are physically separated to minimize power loop inductance and maximize thermal transfer efficiency.

Key Features

Applications

Equivalent & Alternatives

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

Compared with GS66508T and TPH3205WS, the LMG3526R050 uniquely integrates ZVD pulse output and digitally encoded temperature reporting - reducing component count by ≥3 ICs and enabling tighter closed-loop control in high-frequency resonant converters.

Availability

LMG3526R050 is available at Aetrix Electronics and suitable for server PSU, telecom rectifier, and solar inverter applications requiring stable component supply, long-term lifecycle support, and traceable GaN sourcing.

Supply support for LMG3526R050 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 specializing in analog, embedded processing, and power management technologies, with over 90 years of innovation in high-reliability power solutions.

The LMG352x family targets high-efficiency, high-density switch-mode power conversion - specifically engineered to replace silicon MOSFETs in PFC, LLC, and totem-pole topologies where GaN's speed and low Q_OSS deliver measurable system-level gains.

FAQ

What is the function of the ZVD pin on the LMG3526R050?

The ZVD pin (Pin 48) on the LMG3526R050 is a push-pull digital output that pulses when zero-voltage switching is detected during third-quadrant conduction. Its timing is precisely characterized: tDL_ZVD = 15–30ns delay from IN rise, tWD_ZVD = 75–140ns pulse width, and t3rd_ZVD = 42–56ns minimum conduction time required. This signal enables real-time ZVS confirmation in resonant topologies without external sensing circuitry - a key differentiator of the LMG3526R050 versus other GaN FETs.

How does the RDRV pin adjust slew rate on the LMG3526R050?

The RDRV pin on the LMG3526R050 sets gate drive strength by connecting an external resistor to SOURCE: 0Ω yields 150V/ns, 300kΩ yields 15V/ns, and connection to LDO5V yields 100V/ns. This adjustment directly controls turn-on rise time (tr(on) = 2.5–4ns) and enables EMI optimization without changing PCB layout. The LMG3526R050 datasheet provides verified curves showing RDRV resistance vs. slew rate across –40°C to 125°C - confirming deterministic behavior for production validation.

Does the LMG3526R050 require external gate resistors?

No, the LMG3526R050 does not require external gate resistors because its gate driver is fully integrated and slew rate is controlled via the RDRV pin. Unlike discrete GaN FETs or hybrid modules, the LMG3526R050 eliminates gate loop inductance and external component dependencies - reducing parasitic ringing and improving reliability in high-dv/dt applications. This integration is validated in TI's reference designs (e.g., PMP22702) where no gate resistor is present in the LMG3526R050 schematic.

What thermal metrics are specified for the LMG3526R050 package?

The LMG3526R050 specifies RθJC(top) = 0.68°C/W for junction-to-case (top) thermal resistance in its 12mm × 12mm VQFN (RQS) package. This metric is measured with top-side cooling and reflects the device's optimized thermal path through the exposed thermal pad - which is internally connected to SOURCE and NC2 pins. No RθJA or ψ_JT values are specified, as TI recommends top-side heatsinking for production use, consistent with the LMG3526R050's design intent for ultra-thin power systems.

How is temperature reported by the LMG3526R050?

The LMG3526R050 reports junction temperature via a fixed-frequency 9kHz PWM signal on the TEMP pin (Pin 49), where duty cycle encodes temperature: 0.3–6% at 25°C, 36.2–43.7% at 85°C, 58.5–70% at 125°C, and 82% at 150°C. This digital output eliminates analog noise susceptibility and external ADC requirements - enabling direct microcontroller GPIO capture. The LMG3526R050 datasheet confirms this encoding is monotonic and calibrated across –40°C to 150°C, with ±3°C accuracy at 125°C.