Renesas HZ9B1JFA

Overview

HZ9B1JFA from Renesas is a silicon planar Zener diode optimized for low-noise voltage reference and stabilization in precision analog circuits, with a nominal zener voltage of 8.5 V (min 8.3 V, max 8.7 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 low-drift bandgap reference buffers and noise-sensitive instrumentation power rails.

For engineers reviewing the HZ9B1JFA datasheet, HZ9B1JFA pinout, HZ9B1JFA application, or HZ9B1JFA equivalent, key selection criteria include its 60 Ω zener impedance at 0.5 mA, −0.06 %/°C temperature coefficient near 8.5 V, DO-35 package compatibility, and verified low-noise performance versus standard HZ-series diodes.

Technical Context

The HZ9B1JFA operates as a two-terminal voltage reference device using silicon planar Zener breakdown at reverse bias. Its low-noise design reduces RMS noise by approximately 70–90% compared to legacy HZ-series diodes, achieved through optimized doping and junction geometry.

It exhibits a typical zener voltage temperature coefficient of −0.06 %/°C (≈ −5.1 mV/°C) at 8.5 V, enabling stable regulation across −55°C to +125°C ambient range when derated per Fig.3. Reverse leakage remains ≤1 μA at VR = 2.0 V, supporting high-impedance bias networks.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4737A and BZX85C8V2, the HZ9B1JFA delivers tighter V_Z tolerance (±0.2 V vs. ±5%), documented low-noise behavior, and a specified negative temperature coefficient ideal for drift compensation-making it uniquely suited for metrology-grade analog subsystems rather than generic voltage clamping.

Availability

HZ9B1JFA is available at Aetrix Electronics and suitable for high-precision ADC reference design, low-drift op-amp biasing, and stabilized sensor excitation requiring stable component supply and traceable lot-level documentation.

Supply support for HZ9B1JFA 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 SoC solutions for industrial, automotive, and infrastructure markets.

The HZ-L Series was designed specifically for low-noise, high-stability voltage reference applications in precision measurement and instrumentation systems-addressing limitations in noise, temperature drift, and impedance found in earlier Zener families.

FAQ

What is the exact zener voltage range for HZ9B1JFA at 0.5 mA test current?

The HZ9B1JFA has a guaranteed zener voltage range of 8.3 V minimum to 8.7 V maximum when tested at I_Z = 0.5 mA, DC, per Renesas datasheet REJ03G0182-0300 Rev.3.00. This 0.4 V window reflects tight binning for 8.5 V nominal operation and supports applications requiring minimal post-fabrication calibration. The HZ9B1JFA achieves this tolerance via process-controlled junction doping and wafer-level screening.

Does HZ9B1JFA have a specified temperature coefficient, and how does it affect long-term stability?

Yes, the HZ9B1JFA exhibits a typical zener voltage temperature coefficient (γ_Z) of −0.06 %/°C near 8.5 V, equivalent to ≈−5.1 mV/°C. This negative TC enables predictable drift compensation when paired with positive-TC components, improving long-term stability in unregulated environments. The HZ9B1JFA's TC is characterized across 5–38 V variants and confirmed in Figure 2 of the official datasheet.

Can HZ9B1JFA replace standard HZ-series Zener diodes in existing designs without layout changes?

Yes, the HZ9B1JFA uses the identical DO-35 package (GRZZ0002ZB-A) and pinout as legacy HZ-series diodes, with cathode band marking and same mechanical dimensions. No PCB layout changes are required. However, due to its significantly lower noise and tighter V_Z tolerance, the HZ9B1JFA may improve system-level SNR and reduce calibration overhead-making it a direct functional upgrade where low-noise performance is critical.

What is the maximum allowable reverse current before exceeding HZ9B1JFA's power rating?

At T_a = 25°C, the HZ9B1JFA's 400 mW power rating limits the maximum continuous reverse current to approximately 47 mA (400 mW ÷ 8.5 V). However, safe operation requires derating per Figure 3: at 70°C ambient, P_d drops to ~300 mW, reducing max I_Z to ~35 mA. The HZ9B1JFA must be biased below these limits to avoid junction overheating and parameter shift.

Is HZ9B1JFA suitable for use in automotive under-hood applications?

The HZ9B1JFA is rated for junction temperatures up to 175°C and storage from −55°C to +175°C, meeting under-hood thermal requirements. However, Renesas explicitly states that HZ-L Series devices are *not* qualified for automotive safety-critical systems (see Page 5, Note 7). For non-safety automotive applications like cabin sensors or infotainment power rails, the HZ9B1JFA is technically viable but requires customer-level qualification per AEC-Q101 if used in production vehicles.