Nexperia USA Inc. HPZR-C21X

Overview

HPZR-C21X from Nexperia is a high-power Zener voltage regulator diode in CFP3 (SOD123W) package, designed for precision DC voltage clamping and regulation at 21 V nominal working voltage (V_Z = 20.0–22.1 V @ I_Z = 1 mA), with 4.1 W total power dissipation at T_sp = 75 °C and ESD rating of 30 kV per IEC 61000-4-2 (contact discharge). It serves as a stable reference or overvoltage protection element in low-current power rails of industrial sensor interfaces and embedded control modules.

For engineers reviewing the HPZR-C21X datasheet, HPZR-C21X pinout, HPZR-C21X application, or HPZR-C21X equivalent, key selection criteria include its 21 V nominal Zener voltage tolerance (±5 %), differential resistance of 18 Ω @ I_Z = 20 mA, 1 µA max reverse current at V_R, and thermal resistance R_th(j-sp) = 18 K/W to solder point - critical for thermal design in compact SMT layouts.

Technical Context

This device operates as a two-terminal, silicon planar Zener diode optimized for stable reverse-bias breakdown regulation. Its 21 V nominal V_Z is specified at I_Z = 1 mA, with differential resistance of 18 Ω and maximum reverse current of 0.1 µA at rated V_R, ensuring tight voltage stability under light-load conditions.

The CFP3 package enables low-profile mounting with direct thermal coupling via the cathode tab, achieving R_th(j-sp) = 18 K/W - significantly lower than standard SOD-123 - supporting reliable 4.1 W DC power handling at 75 °C solder point temperature without heatsinking.

Key Specifications

Pinout & Package

HPZR-C21X uses the CFP3 (SOD123W) surface-mount plastic package: 2.6 mm × 1.7 mm × 1.0 mm body, flat lead profile, cathode marked by bar on top surface. Thermal performance relies on cathode tab soldering to ≥1 cm² copper pad on FR4 PCB.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C21 and MMSZ5248B, HPZR-C21X delivers >8× higher continuous power, 2.5× lower R_Z, and 2× better thermal coupling - making it the sole option for high-current, thermally demanding Zener regulation without external heatsinking.

Availability

HPZR-C21X is available at Aetrix Electronics and suitable for industrial sensor interfaces, PLC input protection, embedded microcontroller I/O clamping, and DC-DC converter feedback referencing requiring stable component supply and long-term lifecycle support.

Supply support for HPZR-C21X 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 logic, discrete, and MOSFET solutions, with manufacturing rooted in process technology leadership and automotive-grade quality systems.

The HPZR series targets high-power Zener regulation in space-constrained industrial and embedded applications, delivering 4.1 W in CFP3 packaging to replace legacy axial and larger SMD packages while maintaining precision and ruggedness.

FAQ

What is the maximum continuous reverse current HPZR-C21X can regulate at 25 °C ambient?

At T_amb = 25 °C on FR4 PCB with 1 cm² cathode pad, HPZR-C21X supports up to 400 mA continuous reverse current (I_F limit), but practical regulation current is limited by power dissipation: P_tot = 962 mW → I_Z ≈ 45.8 mA at 21 V. Derating applies above 25 °C ambient per Fig. 9.

How does the CFP3 package improve thermal performance versus standard SOD-123?

The CFP3 package features an extended cathode tab that bonds directly to PCB copper, reducing R_th(j-sp) to 18 K/W - 50 % lower than typical SOD-123 (≈35 K/W). This enables 4.1 W DC dissipation at T_sp = 75 °C, whereas standard SOD-123 achieves only ~1.5 W under identical conditions.

Can HPZR-C21X be used in series or parallel configurations for higher voltage or current handling?

Series connection is viable for higher voltage clamping (e.g., 42 V with two units), but requires matched V_Z and thermal coupling to avoid current imbalance. Parallel operation is not recommended due to V_Z tolerance spread and thermal runaway risk - use a single higher-power device instead.

What is the significance of the 30 kV ESD rating, and how is it measured?

The 30 kV rating is per IEC 61000-4-2 contact discharge, verified using ten non-repetitive pulses applied at the cathode solder point. It reflects robustness against human-body ESD events during assembly and field service, eliminating need for supplemental TVS in many I/O protection schemes.