Renesas HZ9A1JTA

Overview

HZ9A1JTA from Renesas is a silicon planar Zener diode optimized for low-noise voltage regulation in precision analog circuits, featuring a nominal zener voltage of 7.9 V (min 7.7 V, max 8.1 V), dynamic resistance of 60 Ω at 0.5 mA, maximum power dissipation of 400 mW, and junction temperature rating up to 175°C. It is used in stabilized power supplies for instrumentation amplifiers and sensor signal conditioning where low noise and stable reference voltage are critical.

For engineers reviewing the HZ9A1JTA datasheet, HZ9A1JTA pinout, HZ9A1JTA application, or HZ9A1JTA equivalent, key selection criteria include its low-noise performance (1/3–1/10 lower than standard HZ series), DO-35 package compatibility, zener voltage tolerance (±0.2 V), temperature coefficient behavior near 7.9 V, and suitability for low-current (<1 mA) precision biasing.

Technical Context

The HZ9A1JTA operates as a two-terminal voltage reference device with cathode-anode polarity, designed for DC-biased operation only (per datasheet note). Its low dynamic impedance (60 Ω) and low leakage current support stable regulation under light-load conditions typical in op-amp feedback networks and ADC reference buffers.

Zener voltage is specified at I_Z = 0.5 mA with ±0.2 V tolerance, and its temperature coefficient is approximately −0.04 %/°C (−3.2 mV/°C) based on Figure 2 of the datasheet for 7.9 V devices - enabling predictable drift compensation in temperature-sensitive analog stages.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C8V2 and 1N4734A, the HZ9A1JTA delivers uniquely low noise at microampere-level currents and precise 7.9 V regulation in a miniature DO-35 package - making it optimal for battery-powered, high-resolution analog signal chains where noise floor and quiescent current dominate selection.

Availability

HZ9A1JTA is available at Aetrix Electronics and suitable for stabilized power supplies, precision sensor interfaces, and low-noise analog reference circuits requiring stable component supply and long-term obsolescence management.

Supply support for HZ9A1JTA 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 Japanese semiconductor manufacturer specializing in microcontrollers, analog and power devices, and system-on-chip solutions for industrial, automotive, and infrastructure markets.

The HZ-L Series Zener diodes were developed specifically for low-noise, high-stability voltage reference applications in precision analog signal conditioning - emphasizing reduced noise density and predictable temperature behavior over raw power handling.

FAQ

What is the exact zener voltage range for HZ9A1JTA?

The HZ9A1JTA has a guaranteed zener voltage range of 7.7 V to 8.1 V when tested at I_Z = 0.5 mA and T_a = 25°C. This ±0.2 V tolerance supports tight 8 V reference designs without post-calibration. The value is measured using DC test conditions per REJ03G0182-0300 Rev.3.00, and the HZ9A1JTA falls within the HZ9A1L subgroup of the HZ-L Series.

Is HZ9A1JTA compatible with DO-35 footprint layouts?

Yes, the HZ9A1JTA uses the standard DO-35 package (JEITA code GRZZ0002ZB-A) with 2.0 mm diameter body and 4.2 mm lead spacing. Its axial leads and orange body with navy blue cathode band match industry-standard DO-35 mechanical dimensions, enabling drop-in replacement in existing through-hole layouts designed for DO-35 Zener diodes.

How does the noise performance of HZ9A1JTA compare to standard Zener diodes?

The HZ9A1JTA achieves approximately 1/3 to 1/10 the noise level of conventional HZ-series Zeners due to optimized silicon planar construction and process control. This reduction is verified in Renesas' characterization data and directly improves signal-to-noise ratio in applications like photodiode biasing and instrumentation amplifier references where the HZ9A1JTA serves as the primary noise source.

What is the maximum reverse leakage current for HZ9A1JTA?

The HZ9A1JTA specifies a maximum reverse leakage current (I_R) of 1 μA at V_R = 2.0 V and T_a = 25°C. This low leakage supports high-impedance bias networks - for example, when used with >1 MΩ resistors in op-amp reference dividers - without introducing measurable offset errors or loading effects in the HZ9A1JTA's regulation path.

Can HZ9A1JTA be used in automotive under-hood applications?

Yes, the HZ9A1JTA supports junction temperatures up to +175°C and storage temperatures from −55°C to +175°C, meeting requirements for non-safety-critical automotive under-hood locations. While Renesas does not qualify the HZ-L Series for AEC-Q200, its thermal ratings and DO-35 robustness make the HZ9A1JTA suitable for engine control module auxiliary references and cabin sensor interfaces where full qualification is not mandated.