Renesas HZS18-1LTD-E

Overview

HZS18-1LTD-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 17.3 V (min 16.9 V, max 17.7 V), 400 mW power dissipation, 15 Ω dynamic impedance at 0.5 mA test current, and ultra-low noise - approximately 1/3–1/10 that of the legacy HZ series. It is used in stabilized power supplies, instrumentation references, and sensor excitation circuits requiring high DC stability.

For engineers reviewing the HZS18-1LTD-E datasheet, HZS18-1LTD-E pinout, HZS18-1LTD-E application, or HZS18-1LTD-E equivalent, key selection criteria include its low-noise zener performance, tight V_Z tolerance (±0.4 V), 200°C maximum junction temperature, MHD package compatibility with 5 mm-pitch automated insertion, and suitability for industrial-grade analog signal conditioning where thermal drift and noise floor are critical.

Technical Context

This device operates as a two-terminal, DC-biased voltage reference using silicon planar junction technology. Its zener breakdown mechanism is optimized for low dynamic resistance (15 Ω) and minimal noise generation across the 0.5–1 mA operating range, with temperature coefficient minimized near 17 V - consistent with the −0.02 to +0.02 mV/°C range observed in the HZS-L family's mid-voltage variants.

The HZS18-1LTD-E is rated for 400 mW total power dissipation at 25°C ambient, derating linearly above 25°C per the published P_d vs. T_a curve, and supports storage from −55°C to +175°C. Its cathode-anode polarity and MHD package geometry align with JEITA standard GRZZ0002ZC-A, enabling direct replacement in legacy HZ-series footprints where low-noise operation is prioritized.

Key Specifications

Pinout & Package

The HZS18-1LTD-E is housed in the MHD package (JEITA code GRZZ0002ZC-A), a radial-leaded, epoxy-molded case with 2.0 mm diameter leads, 26 mm body length, and 2.4 mm pitch - designed for 5 mm-pitch high-speed automatic insertion and compatible with standard through-hole reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4746A and BZX85C18, the HZS18-1LTD-E delivers superior noise performance and tighter V_Z tolerance in a smaller MHD package - making it the preferred choice for precision analog references where spectral purity and initial accuracy are design-critical.

Availability

HZS18-1LTD-E is available at Aetrix Electronics and suitable for industrial power supply references, precision sensor excitation, medical instrumentation references, and test & measurement calibration sources requiring stable component supply with full traceability and lifecycle continuity.

Supply support for HZS18-1LTD-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 specializing in microcontrollers, analog, power, and timing solutions for industrial, automotive, and infrastructure markets.

The HZS-L series was developed by Renesas specifically for low-noise, high-stability voltage reference applications in industrial and instrumentation systems - emphasizing zener noise reduction, thermal robustness, and automated assembly compatibility.

FAQ

What is the exact zener voltage range specified for HZS18-1LTD-E?

The HZS18-1LTD-E has a guaranteed zener voltage range of 16.9 V minimum to 17.7 V maximum at 0.5 mA test current, corresponding to a nominal 17.3 V with ±0.4 V tolerance. This specification is measured under DC conditions per Renesas document REJ03G0166-0300 Rev.3.00 and applies strictly to the HZS18-1L variant - not the -2L or -3L versions.

Does HZS18-1LTD-E have a documented noise spectral density specification?

While Renesas does not publish a numerical noise spectral density (nV/√Hz) value for HZS18-1LTD-E, the datasheet explicitly states its noise level is "approximately 1/3–1/10 lower than the HZ series" - a relative benchmark confirmed across the entire HZS-L family. This performance is achieved via optimized silicon planar junction design and is validated in low-noise reference applications such as precision ADC biasing and sensor excitation circuits using HZS18-1LTD-E.

Is HZS18-1LTD-E RoHS compliant and lead-free?

Yes, HZS18-1LTD-E complies with the EU RoHS Directive and is lead-free. Renesas confirms environmental compliance for the HZS-L series in accordance with applicable regulations, including restriction of hazardous substances. The MHD package uses lead-free solderable terminations and meets JEDEC J-STD-020 moisture sensitivity level (MSL) requirements for standard through-hole assembly processes.

What is the maximum allowable reverse current before exceeding HZS18-1LTD-E's power rating?

At 25°C ambient, the HZS18-1LTD-E's 400 mW power dissipation limit corresponds to a maximum reverse current of approximately 23.2 mA (400 mW ÷ 17.3 V). However, the datasheet specifies test conditions up to 1 mA for dynamic resistance and leakage characterization. For reliable long-term operation, Renesas recommends limiting continuous I_Z to ≤1 mA unless thermal management (e.g., PCB copper area, airflow) is verified to sustain higher currents without exceeding 200°C junction temperature - which requires calculation using the device's thermal resistance and ambient conditions.

Can HZS18-1LTD-E replace older HZ-series zeners in existing designs?

Yes, HZS18-1LTD-E is a direct functional upgrade for HZ18-type zeners in the same MHD package, offering identical pinout, mechanical dimensions, and mounting compatibility. Its lower noise, tighter V_Z tolerance, and improved thermal rating make it suitable for drop-in replacement - provided the application benefits from enhanced noise performance and does not rely on the higher dynamic impedance of legacy HZ parts for intentional damping.