Alpha & Omega Semiconductor Inc. AOD474

Overview

AOD474 from Alpha & Omega Semiconductor is a 75V, 10A N-channel enhancement-mode trench MOSFET in TO-252 (DPAK) package, featuring R_DS(ON) < 130 mΩ at V_GS = 10 V and < 155 mΩ at V_GS = 4.5 V. It is 100% UIS and R_g tested, optimized for high-efficiency boost converters and synchronous rectifiers in consumer, telecom, and industrial power supplies.

For engineers reviewing the AOD474 datasheet, pinout, applications, or equivalent options, key selection criteria include its low R_DS(ON) at 4.5 V gate drive, 100% unclamped inductive switching validation, thermal resistance R_θJC = 5.2 °C/W, and suitability for space-constrained DC-DC topologies requiring robust body-diode performance.

Technical Context

The AOD474 employs advanced trench-gate silicon technology to achieve low on-resistance while maintaining fast switching characteristics: t_D(on) = 5 ns, t_r = 3.5 ns, Q_g(10V) = 6–9 nC, and Q_rr = 52 nC. Its gate threshold voltage (1.2–2.4 V) enables compatibility with 3.3 V and 5 V logic-level drivers.

Thermally, it supports junction temperatures up to 175 °C, with R_θJC = 5.2 °C/W enabling effective heatsinking via the exposed drain pad. The device is rated for repetitive avalanche energy (E_AS) and features a body diode with V_SD = 0.75–1.0 V at I_S = 1 A, critical for synchronous rectification recovery behavior.

Key Specifications

Pinout & Package

Package: TO-252 (DPAK), surface-mount, with exposed drain pad for thermal and electrical connection.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel MOSFET applications.

Compared with STP75NF75 and IRF7470PBF, the AOD474 delivers optimal balance of 10 A current capability, low 4.5 V R_DS(ON), and DPAK thermal performance-making it uniquely suited for compact, self-cooled 20–50 W DC-DC converters where board area and thermal headroom are constrained.

Availability

AOD474 is available at Aetrix Electronics and suitable for boost converters, synchronous rectifiers, and industrial power supplies requiring stable component supply, RoHS-compliant packaging, and production-ready traceability.

Supply support for AOD474 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 & Omega Semiconductor (AOS) is a fabless power semiconductor company specializing in high-performance MOSFETs, IGBTs, and power ICs for computing, consumer, and industrial markets.

The AOD474 belongs to AOS's "Advanced Trench" discrete MOSFET product line, engineered specifically for high-efficiency, high-frequency DC-DC conversion where low gate charge, rugged UIS performance, and thermally efficient packaging are essential.

FAQ

What is the maximum continuous drain current rating for the AOD474 at 100°C case temperature?

The AOD474 supports 7 A continuous drain current at T_C = 100°C, as specified in its Absolute Maximum Ratings table. This derating reflects thermal limits of the TO-252 package and ensures safe operation without exceeding T_J = 175°C. Designers must verify PCB copper area and airflow to sustain this current in actual layouts. The AOD474 datasheet provides de-rating curves in Figure 14 for precise thermal design.

Does the AOD474 support logic-level gate drive at 3.3 V?

The AOD474 has a gate threshold voltage range of 1.2–2.4 V, but its R_DS(ON) is not characterized below V_GS = 4.5 V. At 3.3 V, the device will turn on but exhibits significantly higher on-resistance-unsuitable for power-switching applications. For reliable 3.3 V drive, a logic-level MOSFET with R_DS(ON) specified at 3.3 V (e.g., AOD472) should be selected instead of the AOD474.

Is the AOD474 suitable for use as a synchronous rectifier in an LLC resonant converter?

Yes-the AOD474 is explicitly recommended for synchronous rectification in its General Description, supported by its low Q_rr (52 nC), fast t_rr (14 ns), and body diode V_SD of 0.75–1.0 V. Its TO-252 package enables low-inductance source connections critical for minimizing shoot-through risk in LLC secondary-side layouts. The AOD474's 100% UIS test also enhances reliability during transient overloads.

What is the thermal resistance from junction to ambient (R_θJA) for the AOD474 on a standard PCB?

The AOD474 has R_θJA = 60 °C/W when mounted on a 1 in² FR-4 board with 2 oz. copper in still air, per datasheet Note H. This value assumes minimal copper area and no heatsink. With enhanced PCB copper pours or thermal vias under the exposed drain pad, R_θJA can improve significantly-however, the datasheet specifies R_θJC = 5.2 °C/W as the more reliable metric for heatsink-based designs. The AOD474 thermal data appears on page 2 of its official datasheet.

How does the AOD474's avalanche rating compare to similar 75 V MOSFETs?

The AOD474 is 100% tested for unclamped inductive switching (UIS) with E_AS = 2 mJ at T_J = 25°C, and its single-pulse avalanche capability is graphed in Figure 12 (up to 10 A for 10 µs). Unlike many 75 V MOSFETs rated only for repetitive avalanche, the AOD474's 100% UIS screening ensures each unit meets minimum energy survival-critical for boost converters subject to load-dump or short-circuit events. This makes the AOD474 more robust than non-tested equivalents like the FDP75N75.