Renesas HZ7B3LTD-E

Overview

HZ7B3LTD-E from Renesas Electronics is a silicon planar Zener diode optimized for low-noise voltage regulation in precision analog circuits, featuring a nominal zener voltage of 7.0–7.3 V, 400 mW power dissipation, 60 Ω dynamic resistance at 3.5 mA, and junction temperature rating up to 175°C. It is used in stabilized power supplies, reference voltage sources, and noise-sensitive instrumentation where low diode noise (≈1/3–1/10 that of standard HZ series) and tight voltage tolerance are critical.

For engineers reviewing the HZ7B3LTD-E datasheet, HZ7B3LTD-E pinout, HZ7B3LTD-E application, or HZ7B3LTD-E equivalent, this part serves as a low-noise, DO-35 packaged Zener solution for precision DC voltage stabilization, requiring attention to zener current biasing (0.5–1 mA test condition), thermal derating above 25°C, and cathode-anode polarity in PCB layout.

Technical Context

This device operates as a two-terminal voltage reference using avalanche breakdown in a planar-diffused silicon junction. Its low noise stems from optimized doping profile and geometry, reducing flicker and shot noise components compared to legacy HZ-series diodes. The 60 Ω dynamic impedance at 3.5 mA ensures stable regulation under moderate load transients.

It exhibits a zener voltage temperature coefficient of approximately −0.04 %/°C (−2.8 mV/°C) near 7.2 V, enabling predictable drift compensation in temperature-stable references. The DO-35 package supports through-hole mounting on FR-phenolic PCBs with 2.5 mm lead spacing and 0.5 mm lead diameter.

Key Specifications

Pinout & Package

Package: DO-35 glass axial-leaded package per JEITA code GRZZ0002ZB-A; body color orange; cathode identified by navy-blue band; lead diameter 0.5 mm; overall length 26.0 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 MMBZ5227BLT1G and BZX55C7V5, the HZ7B3LTD-E offers uniquely verified low-noise performance, tighter 7.0–7.3 V zener range, and documented −0.04 %/°C temperature coefficient - making it the preferred choice for metrology-grade references where noise and drift dominate error budgets.

Availability

HZ7B3LTD-E is available at Aetrix Electronics and suitable for stabilized power supplies, precision instrumentation references, medical sensor interfaces, and industrial PLC analog inputs requiring stable component supply with guaranteed long-term continuity.

Supply support for HZ7B3LTD-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 Japanese semiconductor manufacturer specializing in microcontrollers, analog and power devices, and advanced SoCs for industrial, automotive, and infrastructure markets.

The HZ-L Series was designed specifically for low-noise voltage reference applications in precision analog systems, addressing the need for reduced 1/f noise and tighter zener voltage tolerances compared to legacy Zener families.

FAQ

What is the exact zener voltage range for HZ7B3LTD-E at 3.5 mA test current?

The HZ7B3LTD-E has a guaranteed zener voltage range of 7.0 V to 7.3 V when tested at I_Z = 3.5 mA and T_a = 25°C, as specified in the Renesas REJ03G0182-0300 datasheet. This tight 0.3 V window supports high-accuracy voltage referencing without external trimming, and the device is binned to this specific range within the broader HZ7BxL family.

Does HZ7B3LTD-E have a documented noise specification, and how does it compare to standard Zeners?

Yes, the HZ7B3LTD-E datasheet explicitly states its noise level is approximately 1/3 to 1/10 that of the standard HZ series. This reduction results from optimized planar diffusion and junction geometry, yielding lower flicker and shot noise - a key differentiator for HZ7B3LTD-E in audio preamps, precision ADC references, and low-level sensor signal chains where noise floor directly impacts resolution.

What is the maximum allowable zener current for continuous operation of HZ7B3LTD-E at 70°C ambient?

At T_a = 70°C, the HZ7B3LTD-E's power dissipation must be derated from 400 mW. Using the linear derating curve in Figure 3 of REJ03G0182-0300, the allowable P_d drops to ~280 mW. With V_Z ≈ 7.15 V, the maximum continuous I_Z is ~39 mA - though typical bias remains 0.5–1 mA for low-noise operation, well within safe limits.

Is HZ7B3LTD-E RoHS compliant and suitable for lead-free soldering processes?

Yes, HZ7B3LTD-E meets EU RoHS Directive requirements as confirmed by Renesas' environmental compliance documentation. Its DO-35 glass package is compatible with lead-free reflow profiles (peak ≤ 260°C) and standard wave-soldering processes, with no special pre-conditioning needed - consistent with Renesas' "Standard" quality grade designation for industrial and office equipment applications.

How does the temperature coefficient of HZ7B3LTD-E affect its use in a 0–70°C operating environment?

The HZ7B3LTD-E exhibits a zener voltage temperature coefficient γ_Z of approximately −0.04 %/°C (−2.8 mV/°C) near 7.2 V, as shown in Figure 2 of the datasheet. Over a 0–70°C range, this produces a total drift of ~200 mV - manageable in most applications via system-level calibration or complementary NTC compensation, and significantly better than higher-voltage Zeners with positive coefficients above 5.6 V.