Nexperia USA Inc. BZX384-B33F

Overview

BZX384-B33F from Nexperia is a ±2 % tolerance Zener voltage regulator diode in SOD323 (SC-76) package, rated for 33 V nominal breakdown voltage at 2 mA test current, 300 mW total power dissipation, and 45 Ω maximum differential resistance. It serves as a precision reference or overvoltage clamp in low-power analog signal conditioning and power rail stabilization circuits.

For engineers reviewing the BZX384-B33F datasheet, BZX384-B33F pinout, BZX384-B33F application, or BZX384-B33F equivalent, key selection criteria include its 33 V Zener voltage with ±2 % tolerance, 45 Ω dynamic impedance at I_Z = 2 mA, 0.9 V forward voltage at 10 mA, 40 W non-repetitive surge capability, and thermal resistance of 415 K/W junction-to-ambient.

Technical Context

This Zener diode operates in reverse-biased breakdown mode to maintain stable voltage across its terminals under varying load or input conditions. Its regulation performance is defined by tight ±2 % tolerance, low 45 Ω differential resistance, and temperature coefficient of +12.6 mV/K at I_Z = 2 mA - indicating positive drift with rising junction temperature.

The device supports transient suppression via 40 W non-repetitive peak reverse power dissipation (100 μs pulse), while its 300 mW steady-state rating requires thermal management on FR4 PCBs. The SOD323 package enables high-density placement but limits heat dissipation, making it suitable for space-constrained, low-current (<250 mA) regulation tasks.

Key Specifications

Pinout & Package

SOD323 (SC-76) surface-mount plastic package: 2-terminal, cathode-marked with bar, 2.3 mm × 1.35 mm footprint, 0.45 mm height, optimized for reflow soldering per IPC-7095 guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5262B and BZX384-C33, BZX384-B33F delivers superior voltage stability (±2 % vs. ±5 %), lower dynamic impedance (45 Ω vs. 70 Ω/≥65 Ω), and identical surge handling - making it optimal for applications demanding repeatable regulation under variable thermal and load conditions.

Availability

BZX384-B33F is available at Aetrix Electronics and suitable for industrial sensor interfaces, USB-C power delivery protection, automotive body control modules, and low-power microcontroller reference circuits requiring stable component supply and long-term obsolescence management.

Supply support for BZX384-B33F 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 and industrial-grade components.

The BZX384 series belongs to Nexperia's precision Zener regulator product line, engineered specifically for low-power voltage reference and overvoltage protection in space-constrained consumer, industrial, and computing applications.

FAQ

What is the maximum continuous reverse current the BZX384-B33F can sustain?

The BZX384-B33F has no specified maximum continuous reverse current; instead, its steady-state operation is governed by power dissipation limits. At 33 V, sustained regulation requires I_Z ≤ 9.1 mA to stay within the 300 mW P_tot rating at 25 °C ambient. Derating applies above 25 °C per the 415 K/W thermal resistance.

Can BZX384-B33F replace BZX384-A33 in an existing design?

Yes, BZX384-B33F can replace BZX384-A33 if ±2 % tolerance meets system requirements, as both share identical package, thermal characteristics, and Zener voltage center point. However, the A-series offers tighter ±1 % tolerance, so substitution may increase regulation uncertainty by 1 % absolute.

How does temperature affect the 33 V Zener voltage of this diode?

The BZX384-B33F exhibits a +12.6 mV/K temperature coefficient at I_Z = 2 mA, meaning its Zener voltage increases by approximately 12.6 mV per degree Celsius rise in junction temperature. This positive drift must be accounted for in high-accuracy references operating across −40 °C to +125 °C ranges.

Is the SOD323 package suitable for automated optical inspection (AOI) after reflow?

Yes, the SOD323 package features a visible cathode marking bar and consistent coplanarity, enabling reliable AOI detection of solder joint integrity and component orientation. Its standardized footprint and IPC-7351-compliant dimensions support high-yield automated assembly verification.