Nexperia USA Inc. BZX84W-C33-QX

Overview

BZX84W-C33-QX from Nexperia is a ±5% tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 33 V nominal Zener voltage at 2 mA, 325 Ω differential resistance, and 29.7 mV/K temperature coefficient. It delivers 275 mW total power dissipation on FR4 PCB and supports automotive-grade regulation in compact space-constrained circuits.

For engineers reviewing the BZX84W-C33-QX datasheet, BZX84W-C33-QX pinout, BZX84W-C33-QX application, or BZX84W-C33-QX equivalent, key selection factors include its AEC-Q101 qualification, low 0.9 V forward voltage at 10 mA, 45 nA reverse current at 23.1 V, and 0.9 pF junction capacitance at 1 MHz - critical for precision biasing and noise-sensitive analog rails.

Technical Context

This Zener diode operates in reverse breakdown to maintain stable reference voltage under varying load and temperature conditions. Its ±5% tolerance (C-series), 33 V nominal Zener voltage, and 29.7 mV/K positive temperature coefficient enable predictable thermal drift compensation in feedback networks.

Designed for surface-mount use in high-frequency applications, it features 0.9 pF junction capacitance at 1 MHz and 0 V bias, minimizing signal coupling in RF biasing and fast-switching power supply references. The SOT323 package ensures low thermal resistance (455 K/W) and compatibility with standard reflow profiles.

Key Specifications

Pinout & Package

SOT323 (SC-70) leadless surface-mount plastic package with 3 terminals; dimensions: 2.2 mm × 1.35 mm × 0.95 mm (L × W × H), pitch 0.65 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84W-C33-Q, the QX variant adds full traceability without altering performance; versus MMSZ5261B-TP, it trades higher power and lower impedance for automotive qualification and miniaturization - making it optimal for safety-critical, space-constrained designs.

Availability

BZX84W-C33-QX is available at Aetrix Electronics and suitable for automotive ECU design, industrial sensor conditioning, and RF front-end protection requiring stable component supply with full AEC-Q101 compliance and lot-level traceability.

Supply support for BZX84W-C33-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 essential efficiency technologies, delivering high-performance, reliable discrete and logic devices for automotive, industrial, and consumer markets.

BZX84W-Q series belongs to Nexperia's automotive-qualified Zener diode product line, engineered specifically for robust voltage reference and regulation in harsh-environment electronic control units and sensor interfaces.

FAQ

What is the maximum reverse current at 23.1 V for BZX84W-C33-QX?

The reverse current (I_R) is 45 nA at V_R = 23.1 V (0.7 × V_Znom), measured at T_j = 25 °C with pulse duration ≤300 µs. This ultra-low leakage ensures minimal error in high-impedance reference dividers and sensor bias networks.

Does BZX84W-C33-QX support wave soldering?

Yes - Nexperia provides dedicated wave soldering footprint data (Fig. 10) for SOT323: 3.65 mm × 2.1 mm pad layout with 1.425 mm × 0.55 mm solder lands. Thermal profile must limit peak temperature to ≤260 °C for ≤5 seconds to prevent package delamination.

How does the +29.7 mV/K temperature coefficient affect regulation accuracy?

At 33 V nominal, +29.7 mV/K means voltage increases ~0.09% per °C rise. Over a −40 °C to +125 °C range, this yields ±4.9 V drift - compensated in system design via resistor ratio trimming or digital calibration, consistent with AEC-Q101 automotive reference stability requirements.

Is Pin 2 electrically isolated or internally tied to substrate?

Pin 2 is explicitly designated "not connected" (n.c.) in Table 2 and the simplified outline graphic. It is fully isolated - no internal bond wire or die connection - and must remain unconnected on PCB to prevent mechanical stress or unintended coupling in high-frequency layouts.