Renesas HZ3B2J

Overview

HZ3B2J from Renesas is a silicon planar Zener diode engineered for low-noise voltage regulation in precision analog circuits, featuring a nominal zener voltage of 7.0 V (min 6.9 V, max 7.2 V), dynamic resistance of 80 Ω at 0.5 mA test current, maximum power dissipation of 400 mW, and junction temperature rating up to 175°C. It is used in stabilized power supplies and reference circuits where noise suppression and thermal stability are critical.

For engineers reviewing the HZ3B2J datasheet, HZ3B2J pinout, HZ3B2J application, or HZ3B2J 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 (±0.3 V), temperature coefficient behavior near zero crossing (~0 mV/°C at ~7 V), and suitability for low-current biasing in instrumentation-grade references.

Technical Context

The HZ3B2J operates as a two-terminal voltage reference device with a controlled breakdown mechanism optimized for minimal excess noise generation. Its planar construction ensures stable zener impedance and low leakage current (<1 μA at VR = 2.0 V), enabling high-accuracy DC biasing in op-amp feedback networks and sensor excitation circuits.

Designed for operation at low test currents (IZ = 0.5 mA), it delivers predictable regulation across ambient temperatures (−55°C to +175°C storage), with zener voltage temperature coefficient near zero (≈0 mV/°C) - confirmed by Figure 2 of REJ03G0182-0300 - making it ideal for applications requiring minimal drift over temperature.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4732A and BZX55C7V5, the HZ3B2J offers tighter voltage tolerance (±0.15 V vs. ±5%), verified low-noise operation, and optimized tempco at 7 V - making it uniquely suited for precision analog reference roles where noise, drift, and accuracy outweigh raw power handling.

Availability

HZ3B2J is available at Aetrix Electronics and suitable for stabilized power supplies, precision instrumentation references, low-noise audio biasing, and industrial sensor excitation requiring stable component supply and long-term obsolescence management.

Supply support for HZ3B2J 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 and power devices, and system-on-chip solutions for automotive, industrial, and infrastructure markets.

The HZ-L Series Zener diodes were developed specifically for low-noise, high-stability voltage reference applications in precision analog systems - emphasizing reduced excess noise, tight voltage tolerance, and predictable temperature behavior over broad operating conditions.

FAQ

What is the exact zener voltage range for HZ3B2J?

The HZ3B2J has a specified zener voltage range of 6.9 V minimum to 7.2 V maximum, measured at a test current of 0.5 mA and ambient temperature of 25°C. This 0.3 V tolerance window reflects tight binning for precision reference use, distinct from broader-tolerance alternatives like BZX55C7V5. The HZ3B2J datasheet (REJ03G0182-0300, Page 2) confirms this range under DC testing conditions.

Is HZ3B2J suitable for low-current reference designs?

Yes, the HZ3B2J is explicitly characterized at I_Z = 0.5 mA, making it well-suited for ultra-low-power reference circuits such as battery-operated sensors or standby bias networks. Its 80 Ω dynamic resistance and sub-1 μA leakage at 2.0 V reverse bias ensure stable regulation even at microamp-level operating points - a key advantage over higher-current Zeners like the 1N4732A.

Does HZ3B2J have a low-noise specification?

Yes, the HZ-L Series - including HZ3B2J - is documented to deliver approximately 1/3 to 1/10 the noise level of the legacy HZ series, as stated in the "Features" section of REJ03G0182-0300. This low-noise performance is achieved via optimized planar junction design and process control, directly benefiting audio preamps, precision ADC references, and low-level sensor interfaces where noise floor matters.

What is the package type and marking for HZ3B2J?

HZ3B2J uses the DO-35 glass axial package (JEITA code GRZZ0002ZB-A), with an orange body color and a navy blue cathode band. Pin 1 is the cathode (marked end), and Pin 2 is the anode. Package dimensions are defined on Page 5 of REJ03G0182-0300: diameter ≤2.0 mm, length ≥26.0 mm, lead spacing E = 4.2 mm.

How does the temperature coefficient of HZ3B2J compare to other 7 V Zeners?

HZ3B2J exhibits a zener voltage temperature coefficient near 0 mV/°C at its nominal 7 V operating point, as shown in Figure 2 of REJ03G0182-0300. This is significantly more stable than generic 7 V Zeners (e.g., BZX55C7V5 with −2 mV/°C), eliminating the need for external compensation in precision analog circuits where drift must remain below 10 ppm/°C.