Alpha & Omega Semiconductor Inc. AOZ1328DI-01

Overview

AOZ1328DI-01 from Alpha and Omega Semiconductor is a high-side protection switch with true reverse current blocking (TRCB), programmable over-voltage protection (OVP), and auto-restart fault recovery. It operates from 3.4V to 22V input, delivers 9A continuous current with 18mΩ typical R_ON, and targets USB Type-C PD power path protection in portable computing systems.

For engineers reviewing the AOZ1328DI-01 datasheet, pinout, applications, or equivalent options, key selection criteria include its 24V/5.8V selectable OVP threshold, 64ms auto-restart interval, TRCB activation at 26mV V_OUT–V_VIN, thermal shutdown at 140°C, and DFN3x3-12L package with exposed thermal pad for high-current thermal management.

Technical Context

The AOZ1328DI-01 integrates two back-to-back N-channel MOSFETs to enable bidirectional isolation and true reverse current blocking-triggering immediate turn-off when V_OUT exceeds V_VIN by 26mV. Its control logic monitors UVLO (3.35V threshold), OVP (24V or 5.8V selectable via POVP), and die temperature (140°C shutdown with 30°C hysteresis).

Soft-start is externally programmable via CSS capacitor, setting 10%–90% V_OUT ramp time (e.g., 20ms with 5.6nF); fault reporting uses open-drain FLTB with active-low assertion. The device draws only 18µA in shutdown and features ±4kV HBM ESD rating with IEC 61000-4-2 ±8kV on VIN.

Key Specifications

Pinout & Package

AOZ1328DI-01 is housed in a thermally enhanced DFN3x3-12L package with an electrically isolated exposed thermal pad (EXP) serving as the common drain node of internal back-to-back MOSFETs. PCB layout requires multi-layer copper islands connected via vias to EXP for effective heat dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side protection switch applications.

Compared with TPS25750RJER and SiP32411CDN-T1-GE3, the AOZ1328DI-01 uniquely combines true reverse current blocking, selectable OVP, and auto-restart in a thermally optimized DFN3x3-12L package-making it optimal for discrete, high-reliability USB-C power path protection without protocol overhead.

Availability

AOZ1328DI-01 is available at Aetrix Electronics and suitable for USB-C power delivery switches, portable computing power paths, docking station protection, and USB-C dongle designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AOZ1328DI-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 and Omega Semiconductor (AOS) is a fabless power semiconductor company specializing in high-efficiency MOSFETs, power ICs, and advanced packaging for power management applications.

The AOZ1328DI product line delivers high-current, thermally robust protection switches for USB-C PD and portable electronics, emphasizing reliability, programmability, and compact thermal design.

FAQ

What is the OVP threshold configuration for AOZ1328DI-01?

The AOZ1328DI-01 supports two OVP thresholds: 24V when POVP is tied to GND, and 5.8V when POVP is left floating. This selection is implemented via an internal 8µA current source and comparator circuitry-no external resistor is required. The AOZ1328DI-01 datasheet specifies hysteresis of 350mV for both settings, ensuring stable fault clearing.

How does AOZ1328DI-01 implement True Reverse Current Blocking?

The AOZ1328DI-01 detects reverse voltage conditions by monitoring the differential between VOUT and VIN. When VOUT exceeds VIN by 26mV, the internal TRCB circuit triggers immediate turn-off of the back-to-back MOSFETs within 500ns. The FLTB pin asserts low simultaneously, providing real-time fault signaling. This behavior occurs at all times-including during startup and shutdown-and is independent of ENB state.

What is the soft-start timing behavior of AOZ1328DI-01?

The AOZ1328DI-01 uses an external capacitor (CSS) on the SS pin to set soft-start duration. With CSS = 5.6nF, the 10%–90% VOUT ramp time is 20ms at VIN = 20V. The ramp is linear and programmable across input voltages and OVP settings using the formula t_SS = ((V_IN/V_OVP) − 0.0023) × C_SS × 100. Minimum CSS is 0.23nF; values below this risk unstable ramp control.

What thermal design guidance applies to AOZ1328DI-01?

AOZ1328DI-01 requires direct thermal coupling of its exposed pad (EXP) to multi-layer PCB copper islands via ≥8 vias per layer. The EXP pad serves as the common drain node and must be electrically isolated from all other nets. Layout best practice specifies maximum top-layer EXP copper area, isolated inner-layer thermal islands, and bottom-layer thermal pad expansion-achieving θ_JA = 36°C/W and supporting 9A continuous current at +125°C junction.

How does AOZ1328DI-01 differ from AOZ1328DI-02?

The AOZ1328DI-01 implements auto-restart fault recovery with a fixed 64ms retry interval after fault clearance, whereas AOZ1328DI-02 uses latch-off behavior requiring ENB toggle or input power cycle to reset. Both share identical electrical specs, pinout, package, and protection features-including TRCB, OVP, UVLO, and thermal shutdown-but differ exclusively in fault-handling policy and part marking (BG01 vs BG02).