Alpha & Omega Semiconductor Inc. AOZ5332QI-C

Overview

AOZ5332QI-C from Alpha and Omega Semiconductor is a high-current DrMOS power stage module integrating asymmetrical high-side and low-side MOSFETs with an on-die gate driver. It delivers 50A continuous output current, supports up to 2MHz switching, operates from 2.5V–25V input, and features PWM/3V–5V logic compatibility and diode emulation mode via SMOD#. It serves as the power stage in VRMs for high-performance computing and graphics subsystems.

For engineers reviewing the AOZ5332QI-C datasheet, pinout, applications, or equivalent options, key selection criteria include its 50A continuous rating, QFN5x5-31L thermal performance (R_θJC = 2.5°C/W), integrated bootstrap diode, THWN thermal warning output, and Tri-State PWM support for seamless controller interoperability.

Technical Context

The AOZ5332QI-C implements a synchronous buck topology with individually optimized MOSFETs: the high-side device prioritizes low gate charge and capacitance for fast switching at low duty cycles, while the low-side MOSFET features ultra-low R_DS(on) to minimize conduction loss. Its internal driver integrates adaptive dead-time control and shoot-through protection.

It accepts standard CMOS-level PWM inputs (VPWMH = 2.7V, VPWML = 0.72V) and supports Tri-State operation with a defined 1.35V–1.95V window. The module includes under-voltage lockout (3.5V VCC_UVLO), thermal warning (THWN open-drain output triggered at 150°C), and DISB# enable/disable control with internal pull-down resistors.

Key Specifications

Pinout & Package

AOZ5332QI-C uses a low-profile 5mm × 5mm QFN-31L package with exposed VIN and PGND thermal pads for enhanced power dissipation. Pin layout is optimized to minimize parasitic inductance in high-di/dt paths, with grouped VIN (pins 8–11), PGND (pins 12–15, 28, 26, etc.), and multiple parallel VSWH (pins 16–25) terminals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DrMOS power stage applications.

Compared with AOZ5332QI-C, the TDA21472 demands additional external components for bootstrap functionality and offers no thermal alert, while the NCP3232M trades 10A current capacity and 500kHz frequency headroom for reduced feature set-making AOZ5332QI-C optimal for high-performance, thermally aware VRM designs.

Availability

AOZ5332QI-C is available at Aetrix Electronics and suitable for memory and graphic cards, VRMs for motherboards, and point-of-load DC/DC converters requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for AOZ5332QI-C 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

Alpha and Omega Semiconductor (AOS) is a fabless power semiconductor company specializing in MOSFETs, IGBTs, and integrated power solutions for high-efficiency power conversion.

The AOZ5332QI-C belongs to AOS's DrMOS product line, engineered specifically for high-current, high-frequency VRM applications in computing, graphics, and gaming infrastructure where thermal density and transient response are critical.

FAQ

What is the maximum continuous output current rating for AOZ5332QI-C?

The AOZ5332QI-C is rated for 50A continuous output current under standard thermal conditions (T_A = 100°C, recommended PCB layout). This rating assumes proper copper pour, thermal vias under VIN and PGND pads, and adequate airflow or heatsinking. Peak ratings of 80A (10ms) and 120A (10µs) are specified for short-duration transients, such as CPU turbo bursts. Derating applies above 100°C ambient or with suboptimal thermal design.

Does AOZ5332QI-C require an external bootstrap diode?

No, AOZ5332QI-C integrates the bootstrap diode internally. The BOOT pin connects directly to a 100nF ceramic capacitor placed between BOOT and PHASE (pin 7), eliminating the need for an external diode. This reduces component count, improves reliability, and simplifies layout-especially critical in high-density VRM designs where routing space is limited and parasitic inductance must be minimized.

How does the SMOD# pin affect AOZ5332QI-C operation?

The SMOD# pin enables diode emulation or skip mode when pulled low, allowing the low-side MOSFET to behave like a freewheeling diode during light-load or pre-bias conditions. This improves light-load efficiency and enables safe startup into pre-biased outputs. When SMOD# is high, AOZ5332QI-C operates in standard synchronous mode with complementary PWM-driven gate signals. Internal 850kΩ pull-down ensures default DCM behavior if left unconnected.

What is the function of the THWN pin on AOZ5332QI-C?

The THWN pin is an open-drain thermal warning output that pulls low when the internal junction temperature reaches 150°C. It remains asserted until temperature falls to 120°C (30°C hysteresis). AOZ5332QI-C continues operating during THWN assertion-it does not shut down. System designers typically pull THWN up to VCC via a resistor and monitor it with a microcontroller or PMIC to initiate thermal throttling or fan speed adjustment before reaching critical limits.

Is AOZ5332QI-C compatible with 3V PWM controllers?

Yes, AOZ5332QI-C is fully compatible with 3V CMOS logic PWM controllers. Its VPWMH threshold is 2.7V (min) and VPWML is 0.72V (max), ensuring reliable recognition of 3V logic highs and lows. It also supports Tri-State operation with a defined 1.35V–1.95V floating window, allowing seamless interface with controllers that tri-state their PWM outputs during sleep or fault conditions-no level-shifting circuitry is required.