onsemi NZQA6V8AXV5T1G

Overview

NZQA6V8AXV5T1G from onsemi is a quad unidirectional ESD protection diode in SOT-553 package, featuring 4.3 V working peak reverse voltage, 7.14 V maximum breakdown voltage at 1 mA, 13 A peak pulse current, 12 V clamping voltage at 13 A, and <1 µA reverse leakage at VRWM - deployed for USB 1.1 low/full-speed port protection in notebooks and portable equipment.

For engineers reviewing the NZQA6V8AXV5T1G datasheet, pinout, applications, or equivalent options, key selection criteria include IEC 61000-4-2 Level 4 ESD compliance, low clamping voltage under 8 kV contact discharge, four-line integration in 1.6 × 1.2 mm footprint, and USB signal integrity preservation via 6.7 pF typical capacitance at 0 V bias.

Technical Context

This device implements four independent unidirectional ESD clamping paths in a single SOT-553 package, each with a Zener-based avalanche structure optimized for fast response to ±8 kV IEC 61000-4-2 contact discharge events. It operates with a 4.3 V stand-off voltage and clamps to ≤12 V within 1 ns of surge onset.

The diode array is designed for low-capacitance signal line protection: 6.7 pF (typ) at 0 V and 9.5 pF (max) at 3 V bias ensures minimal distortion on USB 1.1 data lines (up to 12 Mbps), while maintaining thermal robustness with 327 °C/W junction-to-ambient resistance on FR-4 board.

Key Specifications

Pinout & Package

SOT-553 (Case 463B), 1.60 mm × 1.20 mm × 0.55 mm body, 0.50 mm pitch, Pb-free, marked "6H" + date code. Five-terminal surface-mount package with internal quad-diode configuration.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ESD protection applications.

Compared with NZQA6V8AXV5T1G, ESZ5Z3.3T5G increases layout complexity and parasitic inductance across four lines, while TPD2E001DRYR trades off USB compliance and lower capacitance for smaller per-channel footprint - making NZQA6V8AXV5T1G optimal for integrated quad-line USB 1.1 protection.

Availability

NZQA6V8AXV5T1G is available at Aetrix Electronics and suitable for USB port protection, serial interface hardening, notebook internal bus safeguarding, and embedded controller interface shielding requiring stable component supply and verified ESD performance.

Supply support for NZQA6V8AXV5T1G 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and edge applications.

The NZQA6V8AXV5T1G belongs to onsemi's ESD protection diode family, engineered specifically for high-density, low-capacitance transient suppression on high-speed digital interfaces including USB, UART, and SMBus.

FAQ

What is the primary function of the NZQA6V8AXV5T1G?

The NZQA6V8AXV5T1G is a quad unidirectional ESD protection diode designed to clamp transient overvoltages on four independent signal lines. Its core function is to divert ±8 kV IEC 61000-4-2 ESD strikes away from sensitive downstream ICs while maintaining signal integrity - a role confirmed by its 6.7 pF capacitance and 12 V clamping voltage. The NZQA6V8AXV5T1G achieves this using Zener-based avalanche structures in a compact SOT-553 package.

Does the NZQA6V8AXV5T1G support USB 1.1 full-speed operation?

Yes, the NZQA6V8AXV5T1G is explicitly validated for USB 1.1 low-speed (1.5 Mbps) and full-speed (12 Mbps) compliance per the onsemi datasheet. Its 6.7 pF typical capacitance at 0 V bias and 9.5 pF maximum at 3 V bias ensure minimal signal distortion on D+/D− lines, and its 4.3 V working peak reverse voltage aligns with USB voltage tolerances. This makes the NZQA6V8AXV5T1G suitable for direct placement on USB connectors in notebooks and peripherals.

What is the pin configuration of the NZQA6V8AXV5T1G?

The NZQA6V8AXV5T1G uses a five-pin SOT-553 package with pinout: Pin 1 = Anode 1, Pin 2 = Common Cathode, Pin 3 = Anode 2, Pin 4 = Anode 3, Pin 5 = Anode 4. This configuration supports four unidirectional protection paths sharing a grounded cathode node - ideal for protecting differential pairs and auxiliary lines like VBUS sense or ID detection. The NZQA6V8AXV5T1G pinout is defined in the mechanical drawing CASE 463B, Style 3.

Is the NZQA6V8AXV5T1G still in active production?

No, the NZQA6V8AXV5T1G is marked as discontinued in the official onsemi datasheet (Rev. 9, September 2025), with ordering information listing it as "DISCONTINUED (Note 6)". While legacy stock may exist, Aetrix Electronics provides traceable sourcing and lifecycle coordination support for the NZQA6V8AXV5T1G to assist customers managing obsolescence in existing designs.

How does the NZQA6V8AXV5T1G compare to bidirectional ESD diodes?

The NZQA6V8AXV5T1G uses unidirectional clamping architecture, requiring a common cathode tied to ground - unlike bidirectional diodes that protect AC-coupled lines without reference. This gives the NZQA6V8AXV5T1G lower leakage (<1 µA) and tighter clamping (12 V vs typical 15–20 V), but mandates DC-biased signal paths. For USB 1.1, which uses DC-coupled D+/D− with pull-ups, the NZQA6V8AXV5T1G delivers superior protection margin and signal fidelity.