Alpha & Omega Semiconductor Inc. AOZ8844DT

Overview

AOZ8844DT from Alpha and Omega Semiconductor is an ultra-low capacitance transient voltage suppressor (TVS) array designed to protect four high-speed differential I/O lines-such as HDMI 1.3, USB 3.0, MDDI, SATA, and Gigabit Ethernet-from ESD, EFT, and lightning surges. It features 0.26 pF line-to-line capacitance, ±15 kV contact/±20 kV air IEC 61000-4-2 ESD rating, 5.0 V working peak reverse voltage, and clamping voltage ≤6.5 V at 5 A (8/20 µs), enabling signal integrity up to 6 GHz in digital TV, set-top box, and notebook applications.

For engineers reviewing the AOZ8844DT datasheet, pinout, applications, or equivalent options, key selection criteria include its DFN-5 package footprint, flow-through I/O layout for minimal trace discontinuity, low clamping voltage under surge, guaranteed 0.26 pF capacitance at 1 MHz, and compliance with IEC 61000-4-2/4-4/4-5 and HBM ±24 kV standards.

Technical Context

The AOZ8844DT integrates eight surge-rated steering diodes and one internal TVS in a single 5-pin DFN package, configured to protect four bidirectional data lanes via symmetrical clamping to V_CC or GND. Its architecture enables fast transient response with low parasitic inductance, critical for preserving signal integrity on 5+ Gbps interfaces.

It operates across –40°C to +85°C ambient temperature, supports 5.0 V working voltage with 6.0 V minimum breakdown, and delivers ≤3.5 V clamping at 2 A and ≤6.5 V at 5 A per IEC 61000-4-5, ensuring robust protection without compromising high-frequency insertion loss (≤–5 dB up to 10 GHz).

Key Specifications

Pinout & Package

AOZ8844DT uses a RoHS-compliant, halogen-free 1.3 mm × 0.8 mm × 0.4 mm DFN-5 package with exposed thermal pad (no internal connection). The pinout supports flow-through routing for HDMI/USB 3.0 differential pairs, minimizing stubs and impedance discontinuities.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar TVS array applications.

Compared with SMA6J5.0A-Q and TPD4E05U06DQAR, the AOZ8844DT uniquely combines 0.26 pF capacitance, flow-through DFN-5 pinout, and 6.5 V clamping in a single device-enabling compact, high-fidelity protection for 5+ Gbps differential interfaces without signal path compromise.

Availability

AOZ8844DT is available at Aetrix Electronics and suitable for HDMI 1.3, USB 3.0, and MDDI interface designs requiring stable component supply, consistent RoHS/halogen-free compliance, and production-ready tape-and-reel packaging (8 mm carrier tape, ø178 mm reel).

Supply support for AOZ8844DT 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, TVS diodes, and power ICs for efficiency-critical applications in computing, consumer, and industrial markets.

The AOZ8844DT belongs to AOS's ultra-low-capacitance TVS array product line, engineered specifically to meet the signal integrity and ESD immunity demands of multi-gigabit serial interfaces-including HDMI, USB 3.0, and MDDI-without requiring layout compromises.

FAQ

What is the maximum operating ambient temperature for AOZ8844DT?

The AOZ8844DT is rated for an ambient temperature range of –40°C to +85°C, making it suitable for deployment in consumer electronics such as digital TVs, set-top boxes, and notebook computers where enclosure temperatures may rise significantly during sustained operation. Its junction temperature can reach +125°C, providing thermal headroom for short-term power surges. This rating is verified per AOS Rev. 3.0 datasheet, Page 2.

Does AOZ8844DT support USB 3.0 Gen 1 (5 Gbps) signal integrity?

Yes, the AOZ8844DT supports USB 3.0 Gen 1 signal integrity with a measured line-to-line capacitance of 0.26 pF at 1 MHz and insertion loss ≤–5 dB up to 10 GHz, as confirmed in the AOZ8844 Rev. 3.0 datasheet Figures 4 and 5. Its flow-through pinout eliminates stubs, preserving eye diagram margins at 5 Gbps. No external matching components are needed.

How many I/O lines does AOZ8844DT protect, and what is the channel configuration?

The AOZ8844DT protects four high-speed differential I/O lines-equivalent to two full differential pairs-using an integrated array of eight steering diodes and one shared TVS. It is configured for bidirectional clamping to V_CC or GND, supporting protocols including HDMI, USB 3.0, MDDI, and SATA. Pin assignments (Pins 1/4 for one pair, Pins 2/3 tied to V_CC/GND) are optimized for straight-through routing.

Is AOZ8844DT RoHS compliant and halogen free?

Yes, the AOZ8844DT is both RoHS compliant and halogen free, as explicitly stated in the AOS Green Products policy and confirmed on Page 2 of the Rev. 3.0 datasheet. It uses reduced-halogen materials meeting JEDEC JS709B and IEC 61249-2-21 standards, and is supplied in a DFN-5 package with lead-free matte tin plating.

What is the clamping voltage of AOZ8844DT under IEC 61000-4-5 5 A (8/20 µs) surge conditions?

The AOZ8844DT has a maximum clamping voltage of 6.5 V under IEC 61000-4-5 5 A (8/20 µs) surge conditions, as specified in the Electrical Characteristics table on Page 3 of the Rev. 3.0 datasheet. This value ensures downstream PHY circuits remain within safe operating voltage limits during lightning-induced transients, with margin below typical 7 V absolute maximum ratings.