Renesas HZ18-3LTD-E

Overview

HZ18-3LTD-E from Renesas Electronics is a silicon planar Zener diode optimized for low-noise voltage reference and stabilization in precision analog circuits, featuring a nominal zener voltage of 18.1–19.0 V at 0.5 mA, 400 mW power dissipation, 80 Ω dynamic impedance, and DO-35 glass package with navy-blue cathode band. It serves as a stable shunt reference in low-drift power supplies and sensor biasing networks where noise suppression is critical.

For engineers reviewing the HZ18-3LTD-E datasheet, HZ18-3LTD-E pinout, HZ18-3LTD-E application, or HZ18-3LTD-E equivalent, this device is selected for its verified low-noise performance (≈1/3–1/10 of standard HZ series), tight zener voltage tolerance, and thermal stability across industrial ambient ranges - key considerations for high-fidelity instrumentation and regulated DC-DC feedback paths.

Technical Context

This Zener diode operates in reverse breakdown mode with DC-tested zener voltage specification under 0.5 mA test current and exhibits a temperature coefficient of approximately −0.04 %/°C near 18 V, confirmed by Figure 2 in REJ03G0182-0300 Rev.3.00. Its low leakage (<1 μA at VR = 15 V) and low dynamic resistance (80 Ω max at IZ = 0.5 mA) support stable regulation under light-load and low-current conditions.

The device uses a silicon planar construction with glass-passivated junction and is rated for junction temperatures up to 175°C. It is specified for Standard-grade applications per Renesas quality classification, suitable for office equipment, test instruments, and industrial control systems - not for automotive, medical, or safety-critical use without explicit approval.

Key Specifications

Pinout & Package

Package: DO-35 (JEITA code GRZZ0002ZB-A), glass axial-leaded, orange body with navy-blue cathode band. Mass: 0.13 g. Dimensions per Page 5: φD = 2.0 mm (max), E = 4.2 mm (max), L = 26.0 mm (min).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5246BS-7-F and BZX84-C18LT1G, the HZ18-3LTD-E delivers superior noise performance and higher power margin in through-hole DO-35 form factor - making it the preferred choice for legacy industrial designs and noise-critical analog subsystems where board real estate permits axial leaded components.

Availability

HZ18-3LTD-E is available at Aetrix Electronics and suitable for industrial power supplies, precision sensor interfaces, test equipment calibration, and audio signal conditioning requiring stable component supply with full traceability and long-lifecycle support.

Supply support for HZ18-3LTD-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 Corporation is a global semiconductor leader delivering microcontrollers, analog power, and timing solutions for industrial, automotive, and infrastructure markets.

The HZ-L Series Zener diodes were designed specifically for low-noise, high-stability voltage reference applications in test and measurement, instrumentation, and industrial control systems - addressing demand for tighter tolerances and lower noise than legacy HZ-family devices.

FAQ

What is the exact zener voltage range for HZ18-3LTD-E at 0.5 mA test current?

The HZ18-3LTD-E has a guaranteed zener voltage range of 18.1 V to 19.0 V when measured at I_Z = 0.5 mA and T_a = 25°C, as specified in the Electrical Characteristics table on Page 3 of REJ03G0182-0300 Rev.3.00. This 0.9 V window reflects factory binning for tight regulation accuracy, and the typical value is centered near 18.55 V.

Is HZ18-3LTD-E suitable for automotive applications?

No, HZ18-3LTD-E is classified as a Standard-grade Renesas product and is not qualified for automotive use. Per Renesas quality grading (Page 1, Note 7), it is intended for computers, office equipment, test instruments, and industrial robots - not transportation equipment. For automotive applications, Renesas offers separate AEC-Q200-qualified Zener families not including the HZ-L series.

What is the maximum allowable junction temperature for HZ18-3LTD-E?

The absolute maximum junction temperature for HZ18-3LTD-E is +175°C, as stated in the Absolute Maximum Ratings table on Page 2 of REJ03G0182-0300 Rev.3.00. Derating begins above 25°C ambient, with full 400 mW power dissipation permitted only at T_a ≤ 25°C; operation beyond this requires thermal analysis using the curve in Figure 3 (Page 4).

Does HZ18-3LTD-E have a documented noise spectral density specification?

The HZ18-3LTD-E datasheet does not list numerical noise spectral density (e.g., nV/√Hz), but explicitly states its noise level is "approximately 1/3–1/10 lower than the HZ series" (Page 1, Features). This comparative claim is validated across the HZ-L family and confirmed by Renesas' internal characterization - making it a documented low-noise Zener, though absolute values require bench measurement per application.

What is the cathode identification method for HZ18-3LTD-E?

HZ18-3LTD-E uses a navy-blue cathode band located near one end of the orange glass DO-35 package body, as shown in the Pin Arrangement diagram on Page 1 of REJ03G0182-0300 Rev.3.00. Pin 1 (cathode) is the lead adjacent to this band; Pin 2 (anode) is the opposite lead. This marking is consistent across all HZ-L Series devices.