Nexperia USA Inc. BZX384-C20/DG/B3X

Overview

BZX384-C20/DG/B3X from Nexperia is a ±5 % tolerance Zener voltage regulator diode in SOD323 (SC-76) package, rated for 20 V nominal breakdown voltage at 5 mA, 300 mW total power dissipation, and 150 °C maximum junction temperature. It provides stable reference voltage in low-power linear regulators and overvoltage protection circuits for consumer and industrial power management ICs.

For engineers reviewing the BZX384-C20/DG/B3X datasheet, BZX384-C20/DG/B3X pinout, BZX384-C20/DG/B3X application, or BZX384-C20/DG/B3X equivalent, key selection criteria include its 20 V ±5 % Zener voltage tolerance, 225 Ω max differential resistance at IZ = 5 mA, 55 μA reverse current at VR = 18.8 V, and suitability for space-constrained PCB layouts requiring SOD323 footprint compliance.

Technical Context

This Zener diode operates in reverse-biased breakdown mode to maintain a stable DC reference voltage across its terminals under varying load and supply conditions. Its regulation performance is defined by specified test current (IZ = 5 mA), differential resistance (rdif ≤ 225 Ω), and temperature coefficient (SZ = +0.05 mV/K).

The device complies with IEC 60134 absolute maximum ratings, supports non-repetitive peak reverse power dissipation up to 40 W (tp = 100 μs), and exhibits thermal resistance from junction to ambient of 415 K/W on standard FR4 PCB - enabling reliable operation in ambient temperatures from –65 °C to +150 °C.

Key Specifications

Pinout & Package

The BZX384-C20/DG/B3X is housed in a SOD323 (SC-76) surface-mount plastic package measuring 1.8 mm × 1.35 mm × 0.95 mm, with cathode marked by a bar on the top surface. Thermal resistance from junction to solder point is 110 K/W, optimized for reflow-soldered FR4 PCBs with standard footprint per Figure 12.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5242B, BZX384-C20/DG/B3X saves 0.4 mm² PCB area and reduces thermal resistance by 35 K/W on FR4; compared with BZX384-B20, it trades 3 % voltage accuracy for lower procurement cost in non-critical biasing roles.

Availability

BZX384-C20/DG/B3X is available at Aetrix Electronics and suitable for power supply reference, overvoltage clamp, and microcontroller reset circuits requiring stable component supply, consistent parametric performance, and long-term obsolescence mitigation.

Supply support for BZX384-C20/DG/B3X 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 leading global semiconductor manufacturer headquartered in Nijmegen, Netherlands, specializing in high-volume logic, discrete, and MOSFET solutions for automotive, industrial, and consumer markets.

The BZX384 series belongs to Nexperia's precision Zener diode product line, engineered for low-power voltage regulation and reference applications where small size, tight thermal response, and robust surge immunity are essential.

FAQ

What is the maximum continuous reverse current this diode can handle?

The BZX384-C20/DG/B3X is rated for a maximum continuous reverse current of 250 mA, derived from its 300 mW power dissipation limit and 20 V Zener voltage (IZ_max ≈ Ptot/VZ = 15 mA at full rating). However, sustained operation above 15 mA requires careful thermal design due to junction temperature rise on standard FR4 PCBs.

Can this Zener diode be used in place of a TVS for ESD protection?

No - while the BZX384-C20/DG/B3X supports 40 W non-repetitive peak reverse power for 100 μs pulses, it lacks the low clamping voltage and fast response (<1 ns) required for IEC 61000-4-2 ESD protection. Dedicated TVS diodes like PESD5V0S1BA have sub-10 V clamping and picosecond response; this Zener is intended for steady-state regulation, not transient suppression.

How does the ±5 % tolerance affect circuit accuracy in a 20 V reference design?

At 20 V nominal, ±5 % tolerance yields a worst-case VZ range of 18.8 V to 21.2 V. In a feedback divider for an adjustable regulator, this introduces up to ±3.1 % output voltage error if uncalibrated. For tighter accuracy, system-level calibration or use of the ±2 % BZX384-B20 variant is recommended.

Is the SOD323 package compatible with standard reflow soldering profiles?

Yes - Nexperia specifies compatibility with JEDEC J-STD-020D reflow profiles. The SOD323 footprint in Figure 12 (0.6 mm pad width, 0.5 mm spacing) supports peak temperatures up to 260 °C for ≤30 seconds. Thermal resistance from junction to solder point is 110 K/W, confirming efficient heat transfer during reflow and steady-state operation.