Renesas HZ18-3-E

Overview

HZ18-3-E from Renesas is a silicon planar Zener diode designed for voltage regulation in stabilized power supplies, with a nominal zener voltage of 18.1–19.0 V at 5 mA test current, 13.0 Ω dynamic resistance, 500 mW power dissipation, and DO-35 glass package. It operates reliably across −55°C to +175°C storage range and supports precision biasing in low-power analog circuits.

For engineers reviewing the HZ18-3-E datasheet, HZ18-3-E pinout, HZ18-3-E application, or HZ18-3-E equivalent, key selection criteria include verified zener voltage tolerance (±0.9 V), low dynamic impedance under 5 mA bias, thermal stability up to 175°C junction temperature, and DO-35 mechanical compatibility with through-hole PCB layouts.

Technical Context

The HZ18-3-E implements a silicon planar junction structure optimized for stable reverse-breakdown operation at 18.1–19.0 V. Its zener voltage exhibits a positive temperature coefficient of approximately +0.06 %/°C near 18 V, confirmed by Figure 2 in REJ03G0180-0600 Rev.6.00.

It is rated for 5 mA zener test current and 1 µA maximum reverse leakage at VR = 14.1 V, with absolute maximum junction temperature of 175°C and storage range spanning −55°C to +175°C - enabling use in industrial ambient environments without derating below 70°C.

Key Specifications

Pinout & Package

DO-35 glass axial package with cathode band marking; total mass ≈ 0.13 g; body diameter φD = 2.0 mm (nom), length L = 26.0 mm (min), lead spacing E = 4.2 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4746A and BZX55-C18, the HZ18-3-E delivers tighter voltage tolerance (±0.9 V vs. ±5%), lower dynamic resistance (13.0 Ω vs. ≥20 Ω), and lower leakage (≤1 µA), making it preferable for high-stability analog references in industrial and automotive systems.

Availability

HZ18-3-E is available at Aetrix Electronics and suitable for industrial power monitors, automotive sensor bias supplies, and programmable logic controller inputs requiring stable component supply with guaranteed long-term continuity and traceable sourcing.

Supply support for HZ18-3-E 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

Renesas Electronics is a global semiconductor manufacturer specializing in microcontrollers, analog power devices, and timing solutions for industrial, automotive, and infrastructure applications.

The HZ Series Zener diodes were developed specifically for high-reliability voltage stabilization in harsh-environment power supplies, emphasizing low leakage, tight voltage grading, and extended temperature capability.

FAQ

What is the exact zener voltage range specified for HZ18-3-E?

The HZ18-3-E has a guaranteed zener voltage range of 18.1 V to 19.0 V when tested at I_Z = 5 mA and T_a = 25°C, per page 4 of REJ03G0180-0600 Rev.6.00. This ±0.45 V tolerance (Grade "-3") is tighter than standard ±5% Zeners and supports precision reference design without trimming. The HZ18-3-E achieves this via Renesas' planar junction process and binning control.

Does HZ18-3-E support operation above 100°C ambient temperature?

Yes - the HZ18-3-E is rated for storage from −55°C to +175°C and has a maximum junction temperature of 175°C. Derating curves on page 5 show usable power dissipation down to ~300 mW at 100°C ambient, enabling direct use in engine bay or industrial control cabinet applications without heatsinking. The HZ18-3-E's DO-35 package facilitates thermal transfer via leads in such environments.

What is the reverse leakage current specification for HZ18-3-E?

The HZ18-3-E specifies maximum reverse leakage current of 1 µA at V_R = 14.1 V and T_a = 25°C, per page 4 of the datasheet. This low leakage ensures minimal error in high-impedance reference dividers and preserves battery life in always-on monitoring circuits. The HZ18-3-E achieves this via optimized silicon processing and strict screening.

Is HZ18-3-E compatible with automated through-hole assembly?

Yes - the HZ18-3-E uses the industry-standard DO-35 axial package (JEITA code GRZZ0002ZB-A) with 2.5 mm lead spacing and 4.2 mm E dimension, fully compatible with standard wave soldering and selective soldering equipment. Its 0.13 g mass and glass body meet IPC-A-610 Class 2 mechanical robustness requirements for HZ18-3-E in high-volume manufacturing.

How does the temperature coefficient of HZ18-3-E compare to other 18 V Zeners?

Per Figure 2 in the datasheet, the HZ18-3-E exhibits a zener voltage temperature coefficient of approximately +0.06 %/°C near 18 V - significantly better than typical 18 V Zeners (often +0.08–0.10 %/°C). This lower drift minimizes output error across temperature in precision regulators. The HZ18-3-E's coefficient is confirmed by Renesas' characterization across the full 18.1–19.0 V grade band.