Alpha & Omega Semiconductor Inc. AOZ1381DI-01

Overview

AOZ1381DI-01 from Alpha & Omega Semiconductor is a dual-mode USB Type-C Power Delivery protection switch integrating independent sink and source back-to-back N-channel MOSFETs in a single DFN-20L package. It delivers 5.5A continuous sink current (32mΩ R_ON) and 3.5A programmable source current (39mΩ R_ON), with True Reverse Current Blocking, Fast Role Swap support, and ±8kV IEC 61000-4-2 ESD protection - deployed in notebook and ultrabook PD power paths.

For engineers reviewing the AOZ1381DI-01 datasheet, pinout, applications, or equivalent options, key selection considerations include sink/source mode isolation, TRCB trip thresholds (44mV sink / 25mV source), auto-recovery fault behavior, FON-controlled FRS timing (≤100µs), and thermal shutdown at 140°C with 30°C hysteresis.

Technical Context

The AOZ1381DI-01 implements two independent, back-to-back N-MOSFET power switches with separate gate drive, charge pump, and protection logic for sink and source operation. Sink mode uses active-low ENB_SNK with programmable soft-start (via CSS) and POVP-configurable OVP (5.8V or 24V); source mode uses active-high EN_SRC, FON-triggered fast turn-on, and ILIM-settable OCP (0.9–3.5A).

Both paths feature True Reverse Current Blocking with asymmetric hysteresis (sink: 44mV trip / 300mV release; source: 25mV trip / 40mV release), open-drain FLTB_SNK/FLTB_SRC fault flags, and shared thermal shutdown at 140°C. The EXP thermal pad is electrically isolated and serves as the common drain node for sink switches.

Key Specifications

Pinout & Package

AOZ1381DI-01 is housed in a 3mm × 5.2mm DFN-20L package with an exposed thermal pad (EXP) that serves as the common drain node for the sink-side MOSFETs and must be electrically isolated and thermally connected to PCB copper via multiple vias.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar USB-C PD dual-mode power switch applications.

Compared with TPS65987D and RT1718S, AOZ1381DI-01 uniquely delivers integrated dual-path switching with FRS-ready timing, independent TRCB thresholds per path, and auto-recovery fault handling - making it the only single-chip solution for compact, low-latency USB-C PD power path management without controller overhead.

Availability

AOZ1381DI-01 is available at Aetrix Electronics and suitable for notebook, ultrabook, and portable monitor designs requiring stable component supply, USB-C PD 3.0 compliance, and Fast Role Swap capability.

Supply support for AOZ1381DI-01 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, power ICs, and advanced packaging for power conversion and protection.

The AOZ1381DI-01 belongs to AOS's USB-C PD power switch product line, engineered specifically for space-constrained, thermally demanding portable systems needing robust bidirectional power path control with minimal external components.

FAQ

What is the function of the EXP thermal pad on AOZ1381DI-01?

The EXP pad on AOZ1381DI-01 is the electrically isolated common drain node for the internal sink-side back-to-back MOSFETs. It must be soldered directly to a dedicated thermal copper area on the PCB and connected to inner-layer thermal planes via multiple vias. This pad is not grounded and must remain floating from signal/power planes to prevent latch-up and ensure safe thermal dissipation under 5.5A sink loads.

How does AOZ1381DI-01 implement True Reverse Current Blocking in sink mode?

AOZ1381DI-01 detects reverse voltage conditions in sink mode by monitoring the differential between VCHG and VBUS. When VCHG exceeds VBUS by ≥44mV, the sink switch turns off within 500ns and pulls FLTB_SNK low. During initial enable or auto-restart, the switch remains off if VCHG > VBUS by ≥44mV - ensuring zero reverse leakage into the USB-C port during battery pre-charge or adapter disconnection.

Can AOZ1381DI-01 support USB PD Fast Role Swap without external timing components?

Yes. AOZ1381DI-01 supports USB PD Fast Role Swap natively via its FON pin: asserting FON high before EN_SRC enables ≤100µs source turn-on with disabled soft-start and suspended OCP. This eliminates need for external timers or controllers - the AOZ1381DI-01 integrates all FRS-critical timing and logic internally, meeting USB PD 3.0 sub-100µs latency requirements.

What is the difference between AOZ1381DI-01 and AOZ1381DI-02?

AOZ1381DI-01 features auto-recovery fault behavior (64ms restart interval after UVLO/OVLO/TRCB), while AOZ1381DI-02 uses latch-off recovery requiring external reset. Both share identical electrical specs, pinout, and thermal performance. AOZ1381DI-01 is recommended for systems needing autonomous fault recovery; AOZ1381DI-02 suits safety-critical applications requiring explicit host acknowledgment before re-enabling.

How is the source current limit programmed on AOZ1381DI-01?

The source current limit on AOZ1381DI-01 is set by connecting an external resistor (R_ILIM) between ILIM and GND. Using R_ILIM = 14.3kΩ yields 1.0A OCP; 7.1kΩ yields 2.0A; and 4.02kΩ yields 3.5A. The relationship is linear: I_LIM ≈ 14.3kΩ / R_ILIM (A). A 1% tolerance resistor is recommended to maintain ±5% current limit accuracy across temperature.