Alpha & Omega Semiconductor Inc. AO3407

Overview

AO3407 from Alpha & Omega Semiconductor is a 30V P-Channel enhancement-mode MOSFET in SOT-23 package, featuring R_DS(ON) < 52 mΩ at V_GS = −10 V and < 87 mΩ at V_GS = −4.5 V, with continuous drain current of −4.1 A. It serves as a low-side load switch or PWM-controlled power switch in DC-DC converters and battery protection circuits.

For engineers reviewing the AO3407 datasheet, pinout, applications, or equivalent options, key selection criteria include verified P-channel logic-level gate drive compatibility, thermal performance under 70°C ambient, body diode recovery characteristics (Q_rr = 5.3 nC), and SOT-23 footprint constraints for space-constrained PCB layouts.

Technical Context

The AO3407 employs trench-gate process technology to achieve low on-resistance and reduced gate charge (Q_g(10V) = 9.2–11 nC), enabling fast switching in high-frequency DC-DC topologies. Its gate threshold voltage range (−1.4 V to −2.4 V) ensures reliable turn-on with standard 3.3 V or 5 V logic-level control signals.

Thermal design relies on junction-to-ambient resistance (R_θJA = 125 °C/W, 1-in² FR-4, 2 oz Cu) and maximum junction temperature of 150 °C. The device supports pulsed drain currents up to −25 A and exhibits body-diode forward voltage of −0.7 V to −1.0 V at −1 A.

Key Specifications

Pinout & Package

SOT-23 package with gull-wing leads; compact 2.9 mm × 1.3 mm footprint, 1.45 mm height, and bottom-side thermal pad not present. Standard pin assignment confirmed per manufacturer top-view diagram.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si2301DDS and DMG2305UVT, the AO3407 offers balanced trade-offs: lower R_DS(ON) than Si2301DDS without the noise-sensitive threshold of DMG2305UVT, making it optimal for general-purpose logic-level P-channel switching where reliability and thermal margin are prioritized.

Availability

AO3407 is available at Aetrix Electronics and suitable for battery management systems, USB power delivery modules, and industrial I/O interfaces requiring stable component supply, long-term lifecycle support, and JEDEC-compliant SOT-23 sourcing.

Supply support for AO3407 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-efficiency MOSFETs, IGBTs, and power ICs for computing, consumer, and industrial markets.

The AO3407 belongs to AOS's logic-level P-channel TrenchMOS™ family, engineered for low-voltage load switching and power management where compact size, low gate drive voltage, and thermal efficiency are essential.

FAQ

What is the maximum continuous drain current for AO3407 at 70°C ambient temperature?

The AO3407 supports −3.5 A continuous drain current at T_A = 70°C, derated from its −4.1 A rating at 25°C due to thermal limitations of the SOT-23 package. This value is specified in the Absolute Maximum Ratings table and reflects safe operation with standard PCB copper area (1 in², 2 oz Cu). Designers must verify board layout thermal performance before operating AO3407 at this current in real-world conditions.

Does AO3407 support 3.3 V logic-level gate drive?

Yes, AO3407 supports 3.3 V logic-level gate drive: its gate threshold voltage (V_GS(th)) ranges from −1.4 V to −2.4 V, and R_DS(ON) is guaranteed < 87 mΩ at V_GS = −4.5 V. While full enhancement occurs at −4.5 V, practical turn-on is achieved with 3.3 V systems when referenced to source-confirming AO3407 suitability for direct MCU GPIO control without level shifters in many low-power applications.

What is the body diode forward voltage of AO3407, and how does it affect flyback converter design?

The AO3407 body diode forward voltage is −0.7 V to −1.0 V at −1 A, as measured with V_GS = 0 V. In flyback converters used as synchronous rectifiers, this low V_SD reduces conduction loss compared to discrete Schottky diodes, but designers must account for reverse recovery charge (Q_rr = 5.3 nC) to avoid shoot-through and EMI during commutation-making AO3407 appropriate only when gate timing precisely controls body diode conduction.

Is AO3407 pin-compatible with other SOT-23 P-channel MOSFETs like Si2301?

AO3407 uses standard SOT-23 pinout (G-S-D), matching Si2301, DMG2305UVT, and most JEDEC-compliant P-channel SOT-23 MOSFETs. However, pin compatibility alone does not guarantee functional equivalence: AO3407's lower R_DS(ON) and distinct V_GS(th) require verification of gate drive strength and thermal margins before substitution. Always validate AO3407 in-system performance prior to design-in.

What thermal resistance values apply to AO3407 in standard PCB mounting?

For AO3407 mounted on a 1 in² FR-4 board with 2 oz copper, R_θJA is 125 °C/W (steady-state) and R_θJL is 0.9 °C/W. These values define junction-to-ambient and junction-to-lead thermal paths, respectively. The 125 °C/W figure assumes still air and governs maximum power dissipation (P_D = 1.4 W at T_A = 25°C); actual thermal performance depends on board copper area, airflow, and adjacent heat sources in the final AO3407 application.