Nexperia USA Inc. BZX84W-C24F

Overview

BZX84W-C24F from Nexperia is a ±5 % tolerance Zener voltage regulator diode rated for 24 V nominal regulation at 5 mA, housed in a SOT323 (SC-70) surface-mount package with anode, cathode, and n.c. terminals. It delivers 275 mW total power dissipation on FR4 PCB, exhibits 250 Ω differential resistance at 5 mA, and maintains stable regulation in high-frequency signal conditioning and low-power supply rail clamping applications.

For engineers reviewing the BZX84W-C24F datasheet, BZX84W-C24F pinout, BZX84W-C24F application, or BZX84W-C24F equivalent, key selection criteria include its 24 V ±5 % Zener voltage, 250 Ω dynamic impedance at I_Z = 5 mA, 275 mW power rating on standard FR4, 55 pF junction capacitance at 1 MHz, and SOT323 thermal resistance of 455 K/W - all critical for precision voltage reference and transient suppression in space-constrained designs.

Technical Context

This Zener diode operates in reverse breakdown to maintain a stable 24 V reference across load variations, with temperature coefficient of +20.4 mV/K at 5 mA enabling predictable drift compensation in ambient ranges from −55 °C to +150 °C. Its non-repetitive peak reverse power capability reaches 40 W for 100 µs pulses, supporting surge immunity in interface protection circuits.

The device features a three-terminal SOT323 package where Pin 1 is anode, Pin 2 is unconnected, and Pin 3 is cathode - ensuring unidirectional conduction and eliminating unintended parasitic paths. Junction-to-ambient thermal resistance of 455 K/W under standard mounting conditions defines its derating envelope for continuous DC operation.

Key Specifications

Pinout & Package

SOT323 (SC-70) leadless surface-mount plastic package with 1.3 mm × 2.2 mm footprint, 0.65 mm pitch, and 0.25 mm thickness - optimized for automated reflow assembly and high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84W-C24F, MMBZ5249BS offers lower dynamic impedance at higher test current but requires higher bias current to achieve spec; BZT52-C24 trades compactness for robustness in thermally demanding environments, making it suitable for industrial power supplies where SOT323 thermal limits are exceeded.

Availability

BZX84W-C24F is available at Aetrix Electronics and suitable for power supply rail clamping, reference voltage generation, ESD protection networks, and high-frequency signal conditioning requiring stable component supply across industrial automation, test equipment, and embedded sensor systems.

Supply support for BZX84W-C24F 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, logic, and MOSFET solutions for automotive, industrial, and consumer markets.

The BZX84W series belongs to Nexperia's general-purpose Zener diode product line, engineered for cost-sensitive, space-constrained regulation and protection tasks in commercial and industrial applications - not qualified for automotive safety-critical use.

FAQ

What is the maximum continuous reverse current the BZX84W-C24F can sustain at 25 °C?

The BZX84W-C24F supports a maximum continuous reverse current of 11.5 mA at 25 °C ambient, calculated from its 275 mW power rating and 24 V Zener voltage (P_tot/V_Z). Derating applies above 25 °C per the 455 K/W thermal resistance, reducing usable current by ~2.4 mA per 10 °C rise in junction temperature.

Can BZX84W-C24F be used in bidirectional ESD protection configurations?

Yes - two BZX84W-C24F diodes connected anode-to-anode form a symmetrical 24 V clamping pair suitable for bidirectional I/O protection. This configuration achieves ~28 V clamping voltage under 8 kV ESD events and leverages the device's 40 W non-repetitive pulse rating, though layout must minimize trace inductance to preserve response time.

How does the ±5 % tolerance affect regulation accuracy in a 24 V reference circuit?

At 24 V nominal, ±5 % tolerance means actual Zener voltage falls between 22.8 V and 25.6 V. In a reference circuit biased at 5 mA, this introduces up to ±0.68 V absolute error. For tighter accuracy, post-regulation trimming or feedback-based compensation is required - the diode itself provides stable relative regulation within its specified band.

Is the n.c. pin in the SOT323 package electrically isolated or internally tied?

Pin 2 is explicitly designated "not connected" in Nexperia's official pinning diagram and has no internal bond wire or silicon connection. It is fully electrically isolated and must remain unconnected on the PCB; routing traces or soldering to this pad risks mechanical stress-induced package cracking or contamination-related reliability degradation.