Nexperia USA Inc. BZX84W-C56X

Overview

BZX84W-C56X from Nexperia is a ±5% tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 56 V nominal Zener voltage at 2 mA, 425 Ω differential resistance, and 57.0 mV/K temperature coefficient; used for precision voltage reference and overvoltage protection in power supply feedback loops and sensor biasing circuits.

For engineers reviewing the BZX84W-C56X datasheet, BZX84W-C56X pinout, BZX84W-C56X application, or BZX84W-C56X equivalent, this page delivers verified electrical parameters, thermal behavior, SOT323 terminal mapping, and real-world use cases for stable 56 V regulation under low-current conditions.

Technical Context

This Zener diode operates in reverse breakdown with a specified Zener voltage of 52.0 V to 60.0 V at I_Z = 2 mA, exhibiting a positive temperature coefficient of +57.0 mV/K - enabling predictable drift compensation in temperature-sensitive references. Its 425 Ω differential resistance ensures stable regulation across small current variations.

Designed for surface-mount operation on FR4 PCBs with single-sided copper, it delivers 275 mW total power dissipation and withstands non-repetitive peak reverse power up to 40 W for 100 µs pulses, supporting transient suppression in compact DC/DC converter designs.

Key Specifications

Pinout & Package

SOT323 (SC-70) leadless plastic surface-mount package with 3 terminals, 1.3 mm × 1.8 mm footprint, and 0.65 mm pitch; optimized for reflow soldering per IPC-7351B standard land pattern.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84W-C56X, BZX84W-B56 offers superior voltage accuracy at identical thermal performance, while MMBZ5256B trades package size for reduced power handling and less predictable temperature drift - making the C56X optimal for new SOT323 designs prioritizing cost, stability, and surge resilience.

Availability

BZX84W-C56X is available at Aetrix Electronics and suitable for power supply feedback reference, sensor biasing circuit, and overvoltage protection clamp applications requiring stable component supply, consistent parametric performance, and long-term manufacturing continuity.

Supply support for BZX84W-C56X 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, headquartered in Nijmegen, Netherlands, with manufacturing in Asia and Europe.

The BZX84W series belongs to Nexperia's general-purpose Zener diode product line, engineered for compact, low-cost voltage regulation in consumer, industrial, and computing power management systems.

FAQ

What is the maximum continuous reverse current the BZX84W-C56X can sustain without degradation?

The device has no defined maximum continuous reverse current; its safe operating area is governed by power dissipation limits. At 25 °C ambient, sustained reverse current must be limited to ≤4.9 mA to stay within the 275 mW P_tot rating (56 V × 4.9 mA ≈ 275 mW). Derating is required above 25 °C per the 455 K/W junction-to-ambient thermal resistance.

Does the 'n.c.' pin on the SOT323 package require PCB connection or thermal relief?

No - Pin 2 is internally not connected and electrically isolated. It must remain unconnected on the PCB; adding a copper pour or thermal relief to this pad may alter thermal dissipation characteristics and is not recommended. The datasheet explicitly defines it as "not connected" with no functional or thermal role.

How does the +57.0 mV/K temperature coefficient affect regulation accuracy over −40 °C to +125 °C ambient?

Across this range, junction temperature rise causes Zener voltage to increase by up to +9.7 V (57.0 mV/K × 170 K), shifting V_Z from ~52 V to ~61.7 V. For stable reference use, this drift must be compensated in system design - e.g., via complementary NTC networks or digital calibration - as the diode itself provides no internal compensation.

Can BZX84W-C56X replace BZX84-C56 in existing SOT23 designs?

No - BZX84W-C56X uses SOT323 (SC-70) packaging (1.3 mm × 1.8 mm), while BZX84-C56 uses SOT23 (3.0 mm × 1.4 mm). Footprint, pad layout, and thermal mass differ significantly; direct replacement requires PCB redesign. Electrical specs are similar, but mechanical incompatibility prevents drop-in substitution.