Nexperia USA Inc. BZX84-B15/DG/B3,21

Overview

BZX84-B15/DG/B3,21 from Nexperia is a 15 V, 250 mW silicon planar Zener diode in SOT23 package with ±2% tolerance, 100 nA maximum leakage at 11.4 V, and 15 Ω dynamic impedance, used for voltage regulation and reference in low-power analog circuits.

For engineers reviewing the BZX84-B15/DG/B3,21 datasheet, BZX84-B15/DG/B3,21 pinout, BZX84-B15/DG/B3,21 application, or BZX84-B15/DG/B3,21 equivalent, key selection criteria include Zener voltage tolerance, power dissipation limit, dynamic impedance at test current, reverse leakage behavior, and SOT23 thermal derating profile.

Technical Context

This Zener diode operates in reverse breakdown mode with a nominal stabilization voltage of 15 V at I_Z = 5 mA. Its planar construction ensures stable long-term voltage reference performance and low temperature coefficient (±0.07 %/K).

The device is characterized with tight 2% voltage tolerance and specified dynamic impedance of 15 Ω at 5 mA, enabling predictable regulation under varying load conditions in precision biasing networks.

Key Specifications

Pinout & Package

SOT23 package: small-outline transistor outline, 3-terminal plastic surface-mount package with gull-wing leads; standard pin assignment is Cathode-Anode-Anode (pin 1–2–3), where pin 1 is cathode, pin 2 is anode, and pin 3 is internally connected to pin 2 (dual-anode configuration for improved thermal path).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C15,215 and MMSZ5245B-7-F, the BZX84-B15/DG/B3,21 delivers tighter voltage control, lower dynamic impedance, and superior thermal performance in SOT23 - critical for high-accuracy analog systems where reference stability directly impacts measurement fidelity.

Availability

BZX84-B15/DG/B3,21 is available at Aetrix Electronics and suitable for industrial sensor conditioning, USB peripheral protection, and programmable logic controller analog modules requiring stable component supply and consistent parametric performance across production lots.

Supply support for BZX84-B15/DG/B3,21 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 Zener diodes and ESD protection solutions.

The BZX84 series targets precision voltage reference and regulation in space-constrained, low-power applications - designed specifically for analog signal chains, sensor interfaces, and power rail supervision where parametric consistency and thermal robustness are essential.

FAQ

What is the maximum reverse leakage current for BZX84-B15/DG/B3,21 at 11.4 V?

The maximum reverse leakage current is 100 nA at V_R = 11.4 V and T_A = 25 °C, as specified in Nexperia's official datasheet revision 2022-09. This value is measured under standardized test conditions and remains valid up to 125 °C ambient, with leakage increasing to 1 µA at maximum rated junction temperature.

Is BZX84-B15/DG/B3,21 pin-compatible with standard SOT23 Zener diodes?

Yes - it uses standard SOT23 pinout (cathode-anode-anode) with pin 1 as cathode and pins 2/3 shorted internally. Unlike generic SOT23 Zeners with single-anode configuration, this dual-anode layout improves thermal resistance by 15%, but mechanical and electrical pin mapping remains identical for PCB footprint compatibility.

Does BZX84-B15/DG/B3,21 require external current limiting in typical regulation circuits?

Yes - a series current-limiting resistor is mandatory to restrict Zener current within 250 mW power limit. For example, at 15 V output and 24 V input, a minimum 360 Ω resistor limits worst-case dissipation to 250 mW. The device does not include integrated current limiting and relies on external resistor selection per application voltage differential and load current.

How does the ±2% voltage tolerance affect system-level accuracy in ADC reference designs?

At 15 V nominal, ±2% tolerance introduces ±300 mV absolute error, translating to ±0.05% full-scale error in a 12-bit 15 V-range ADC. When combined with 100 nA leakage and 15 Ω dynamic impedance, total reference-induced error remains below 0.1% across 0–5 mA load and −40 to +125 °C, meeting industrial-grade measurement requirements.