STMicroelectronics MASTERGAN4LTR

Overview

MASTERGAN4LTR from STMicroelectronics is a 600 V half-bridge enhancement-mode GaN power system-in-package integrating a high-voltage gate driver and two GaN HEMTs in monolithic QFN 9 × 9 mm. It delivers R_DS(ON) = 225 mΩ (T_J = 25 °C), I_DS(MAX) = 6.5 A, zero reverse recovery charge (Q_RR = 0 nC), and ultrafast wake-up time < 200 ns - enabling high-frequency LLC resonant converters and active clamp flybacks.

For engineers reviewing the MASTERGAN4LTR datasheet, MASTERGAN4LTR pinout, MASTERGAN4LTR application, or MASTERGAN4LTR equivalent, key selection considerations include integrated bootstrap diode (R_DBoot = 140–175 Ω), interlocking logic to prevent cross-conduction, dedicated SD/OD shutdown pin with open-drain overtemperature reporting, and 3.3–15 V logic-compatible inputs with hysteresis.

Technical Context

The device implements a self-contained half-bridge topology with electrically isolated high-side and low-side GaN transistors: low-side drain connected to OUT pins, source tied to SENSE pins; high-side drain connected to VS pins, source tied to OUT pins. The embedded driver uses level-shifted architecture with internal RG_ON/RG_OFF resistors (75 Ω / 2 Ω per side) and fixed timing match between HIN→GH and LIN→GL propagation delays (45 ns typ).

UVLO protection on VCC (4.2–4.75 V turn-on threshold, 0.3 V hysteresis) safeguards operation under marginal supply conditions. The integrated bootstrap circuit charges C_BOOT synchronously with low-side switching, achieving stable V_BO ≥ 4.4 V with typical 33 nF capacitor and < 200 ns wake-up after low-side turn-on.

Key Specifications

Pinout & Package

MASTERGAN4LTR is housed in a thermally enhanced QFN 9 × 9 × 1 mm package with three exposed thermal pads (EP1, EP2, EP3) for low R_th(J-CB) = 2.8 °C/W per GaN transistor. Pin assignment follows STMicroelectronics DS14356 Rev 2 (page 3/26).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar half-bridge GaN power stage applications.

Compared with UCC12050-Q1 (auxiliary bias IC) and NV6136 (discrete-driver GaN half-bridge), MASTERGAN4LTR uniquely combines 650 V GaN switches, gate driver, bootstrap diode, interlocking logic, and overtemperature reporting in one QFN package - reducing BOM count by ≥7 components and eliminating layout-sensitive gate loop routing.

Availability

MASTERGAN4LTR is available at Aetrix Electronics and suitable for high-frequency resonant converters, active clamp flybacks, and high-voltage DC-DC isolated converters requiring stable component supply, long-term lifecycle assurance, and production-ready qualification.

Supply support for MASTERGAN4LTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

MASTERGAN4LTR belongs to ST's MASTERGAN family of GaN-integrated power stages, engineered specifically for high-efficiency, high-frequency AC-DC and DC-DC conversion in compact, thermally demanding applications.

FAQ

What is the maximum recommended switching frequency for MASTERGAN4LTR?

MASTERGAN4LTR is characterized and validated for reliable operation up to 1 MHz, with optimal performance in 300–700 kHz resonant topologies. Its 100 V/ns slew rate, 45 ns propagation delay, and zero Q_RR enable clean ZVS transitions at 500 kHz in LLC converters. Thermal limits (T_J ≤ 125 °C) and gate drive strength constrain practical upper frequency based on PCB thermal design - not device intrinsic limits.

Does MASTERGAN4LTR require external gate resistors?

No. MASTERGAN4LTR integrates fixed 75 Ω turn-on and 2 Ω turn-off gate resistors optimized for its GaN transistors' Q_G (1.5 nC) and target slew rate (100 V/ns). Adding external resistors degrades timing accuracy, increases propagation delay variation, and risks violating the 200 ns wake-up specification. External resistors are unnecessary unless specific EMI tuning is required - and even then, only low-value (<5 Ω) series additions are advised.

How is overtemperature protection implemented?

MASTERGAN4LTR features an internal thermal sensor that triggers shutdown when junction temperature reaches 175 °C (T_TSD). The SD/OD pin acts as open-drain output: when overtemperature occurs, it pulls low to signal the controller. Hysteresis of 20 °C ensures stable re-enablement only after cooling to ≤155 °C. This is distinct from VCC UVLO and operates independently - allowing fault isolation even during normal supply conditions.

Can MASTERGAN4LTR drive a bootstrap capacitor larger than 33 nF?

Yes - larger bootstrap capacitors (e.g., 47–100 nF) improve V_BO ripple suppression and hold-up time, especially at high duty cycles or low switching frequencies. However, charging time increases linearly with capacitance (t_charge ≈ R_DBoot × C_BOOT); using >68 nF may exceed the <200 ns wake-up requirement in high-frequency LLC designs. For such cases, verify V_BO stability under worst-case δ_LS and f_sw using Equation 5 from DS14356 Rev 2.