Nexperia USA Inc. BZX84W-B9V1-QF

Overview

BZX84W-B9V1-QF from Nexperia is a ±2% tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 9.1 V nominal Zener voltage at 5 mA, 275 mW total power dissipation, and qualified to AEC-Q101 for automotive use. It provides stable voltage reference in low-power regulation circuits, ESD protection clamping, and biasing networks in engine control units and body electronics.

For engineers reviewing the BZX84W-B9V1-QF datasheet, BZX84W-B9V1-QF pinout, BZX84W-B9V1-QF application, or BZX84W-B9V1-QF equivalent, key selection criteria include Zener voltage tolerance (±2%), differential resistance (100 Ω max at 5 mA), temperature coefficient (+5.5 mV/K), reverse leakage (500 nA at 6 V), and AEC-Q101 qualification status.

Technical Context

This Zener diode operates in reverse breakdown mode with a nominal 9.1 V regulation voltage at I_Z = 5 mA, exhibiting a positive temperature coefficient of +5.5 mV/K - indicating voltage increases with junction temperature. Its differential resistance of ≤100 Ω ensures tight regulation under varying load currents.

The device features a not-connected (n.c.) terminal (Pin 2), enabling simplified PCB layout while maintaining mechanical robustness in high-frequency applications. Thermal resistance from junction-to-ambient is 455 K/W on standard FR4, limiting continuous power handling to 275 mW at T_amb = 25 °C.

Key Specifications

Pinout & Package

SOT323 (SC-70) surface-mount plastic package with 3 leads, 1.3 mm × 1.8 mm footprint, 0.65 mm pitch, and 0.25 mm lead thickness - optimized for automated placement and reflow soldering on space-constrained PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84W-C9V1-Q, the BZX84W-B9V1-QF offers tighter tolerance and lower impedance for precision applications; versus MMSZ4687T1G, it delivers automotive qualification and smaller footprint at higher cost and power rating.

Availability

BZX84W-B9V1-QF is available at Aetrix Electronics and suitable for automotive engine control, infotainment power management, and ADAS camera stabilization requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for BZX84W-B9V1-QF 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 essential efficiency technologies, delivering high-performance, reliable discrete and logic devices for automotive, industrial, and consumer markets.

The BZX84W-Q series belongs to Nexperia's automotive-qualified Zener diode product line, engineered specifically for stable voltage reference and transient suppression in harsh-environment electronic control units.

FAQ

What is the maximum continuous reverse current this Zener can handle at 9.1 V?

The BZX84W-B9V1-QF has no specified maximum continuous reverse current; its operation is defined by power dissipation limits. At 9.1 V, the absolute maximum steady-state reverse current is 30.2 mA (275 mW ÷ 9.1 V), assuming full derating at 25 °C ambient and no thermal overhead. Actual usable current must be reduced per thermal resistance (455 K/W) to maintain T_j ≤ 150 °C.

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

Pin 2 is electrically not connected (n.c.) - no internal bond wire or semiconductor connection exists. It serves solely as a mechanical anchor for the leadframe in the SOT323 package, improving mounting strength and coplanarity during reflow. No thermal conduction path exists through this terminal; thermal performance relies entirely on Pins 1 and 3 and PCB copper area.

How does the +5.5 mV/K temperature coefficient affect long-term stability in an ECU?

The +5.5 mV/K coefficient means the Zener voltage rises 5.5 mV per Kelvin increase in junction temperature. Over the automotive range (−40 °C to +125 °C), this produces a +907.5 mV shift (165 K × 5.5 mV/K), resulting in a total V_Z span of 8.2 V to 10.0 V. System-level compensation or calibration is required to maintain accuracy within functional safety targets.

Can this diode replace a 9.1 V Zener in a non-automotive design without redesign?

Yes - the BZX84W-B9V1-QF is functionally compatible with any 9.1 V ±2 % Zener application, including commercial and industrial systems. Its SOT323 footprint, electrical specs, and surge capability exceed generic equivalents. However, its AEC-Q101 qualification adds no benefit outside automotive contexts and may incur higher cost than non-qualified alternatives.