Nexperia USA Inc. BZX84W-B6V8-QX

Overview

BZX84W-B6V8-QX from Nexperia is a ±2% tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 6.8 V nominal regulation at 5 mA, with 80 Ω differential resistance and 3.0 mV/K temperature coefficient. It delivers 275 mW total power dissipation on FR4 PCB and supports automotive-grade operation per AEC-Q101.

For engineers reviewing the BZX84W-B6V8-QX datasheet, BZX84W-B6V8-QX pinout, BZX84W-B6V8-QX application, or BZX84W-B6V8-QX equivalent, this part serves as a precision low-power voltage reference in noise-sensitive analog rails, ESD-clamped signal conditioning paths, and automotive body control module bias networks where thermal stability and small-footprint reliability are critical.

Technical Context

This Zener diode operates in reverse breakdown to maintain stable 6.8 V output across load and line variations, with tight ±2% initial tolerance ensuring minimal calibration drift in feedback loops. Its 80 Ω dynamic impedance at 5 mA enables predictable regulation under moderate current transients up to 200 mA forward peak.

The device exhibits a positive 3.0 mV/K temperature coefficient near 6.8 V, minimizing output drift over −55 °C to +150 °C ambient range. Thermal resistance of 455 K/W (junction-to-ambient, FR4 single-sided copper) defines its derating envelope for sustained 275 mW operation.

Key Specifications

Pinout & Package

SOT323 (SC-70) leadless surface-mount plastic package with 3 terminals; compact 2.2 mm × 1.35 mm footprint and 0.65 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener regulation applications.

Compared with MMBZ5235B and BZX84-C6V8, BZX84W-B6V8-QX offers superior regulation accuracy (±2% vs. ±5%), lower dynamic impedance (80 Ω vs. ≥100 Ω), and AEC-Q101 qualification-making it the optimal choice for automotive and industrial systems requiring long-term voltage reference stability without calibration.

Availability

BZX84W-B6V8-QX is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, USB-C ESD protection, and low-power IoT node voltage references requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for BZX84W-B6V8-QX 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

Nexperia is a global semiconductor expert focused on high-volume, high-reliability discrete and logic devices, with leadership in automotive-qualified components and advanced packaging technologies.

The BZX84W-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode product line, engineered specifically for stable voltage regulation in automotive control units, industrial sensors, and portable electronics where space, thermal performance, and long-term reliability are critical.

FAQ

What is the maximum continuous reverse current the BZX84W-B6V8-QX can sustain at 25 °C?

The device is rated for 200 mA maximum forward current, but as a Zener regulator, its continuous reverse (Zener) current is limited by power dissipation. At 25 °C ambient and 275 mW P_tot, the maximum sustainable Zener current is 40.4 mA (275 mW ÷ 6.8 V), assuming full voltage drop across the diode. Derating applies above 25 °C per the 455 K/W thermal resistance.

Can BZX84W-B6V8-QX be used in place of a 6.8 V Zener with ±5% tolerance?

Yes, but with design impact: the tighter ±2% tolerance improves reference accuracy and reduces calibration overhead, while lower 80 Ω differential resistance enhances load regulation. However, the ±5% part may allow higher current before reaching P_tot due to wider V_Z spread-verify worst-case power in your specific bias network.

Is Pin 2 truly unconnected, or does it serve a mechanical or thermal function?

Pin 2 is electrically unconnected (n.c.) per Nexperia's official pinning diagram and internal construction. It has no electrical role and must remain floating in PCB layout. While it contributes to mechanical stability and solder joint integrity, it provides no thermal conduction path-thermal performance relies solely on Pins 1 and 3 and the die attach to the leadframe.

How does the +3.0 mV/K temperature coefficient affect long-term stability in a 0–70 °C operating range?

Over a 70 °C span, the Zener voltage shifts by +210 mV (3.0 mV/K × 70 K), resulting in a 6.8 V nominal output varying from 6.80 V to 7.01 V. This 3.1% drift is predictable and linear, enabling first-order compensation in firmware or analog circuitry-unlike non-monotonic tempcos that require lookup tables or trimming.