Renesas HZU4BLLTRF-E

Overview

HZU4BLLTRF-E from Renesas Electronics is a silicon epitaxial planar Zener diode optimized for hard-knee, low-noise voltage reference applications, with a nominal Zener voltage of 3.9 V (min 3.7 V, max 4.1 V at I_Z = 0.5 mA), dynamic resistance of 370 Ω (typ), and ultra-low noise voltage (~1/3–1/10 that of standard HZU series). It operates in surface-mount URP (Ultra small Resin Package) and is used in precision analog front-ends and low-drift reference circuits.

For engineers reviewing the HZU4BLLTRF-E datasheet, HZU4BLLTRF-E pinout, HZU4BLLTRF-E application, or HZU4BLLTRF-E equivalent, key selection criteria include its semi-logarithmic V_Z-I_Z linearity from 1 nA to 1 mA, temperature coefficient of −0.03 mV/°C (typ), and suitability for low-current, low-noise biasing in instrumentation amplifiers and ADC reference buffers.

Technical Context

The HZU4BLLTRF-E employs a hard-knee Zener breakdown mechanism with epitaxial planar construction to achieve stable, low-hysteresis voltage regulation at microampere-level currents. Its V_Z-I_Z curve exhibits semi-logarithmic linearity across six decades (1 nA–1 mA), enabling predictable behavior in sub-threshold bias networks.

Designed for ultra-low-noise operation, it delivers ~70% lower noise voltage than the legacy HZU series and ~50% lower temperature coefficient (γ_Z ≈ −0.03 mV/°C), making it suitable for high-resolution measurement systems where thermal drift and broadband noise directly impact accuracy.

Key Specifications

Pinout & Package

Package: Ultra small Resin Package (URP), JEITA code PTSP0002ZA-A, Renesas code SC-76A, mass 0.004 g. Dimensions: A1 = 0.75–0.90 mm, A2 = 0.15–0.30 mm, b = 1.55–1.70 mm, D = 0.80 mm, E = 0.80 mm, e1 = 2.30 mm, l1 = 1.10–1.25 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL431ACDBVR and BZX84-C3V9, the HZU4BLLTRF-E provides superior low-noise performance and thermal stability in fixed-voltage, low-current reference roles-making it irreplaceable in applications demanding sub-microvolt drift and femtoampere-level leakage control.

Availability

HZU4BLLTRF-E is available at Aetrix Electronics and suitable for high-resolution data acquisition, precision instrumentation amplifiers, and low-power sensor signal conditioning requiring stable component supply, consistent parametric performance across production lots, and long-term availability for industrial OEM programs.

Supply support for HZU4BLLTRF-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 manufacturer headquartered in Tokyo, Japan, specializing in microcontrollers, analog and power devices, and advanced SoCs for automotive, industrial, and infrastructure markets.

The HZU-LL Series was developed by Renesas specifically for ultra-low-noise, hard-knee Zener reference applications in high-accuracy analog signal chains-targeting metrology, medical instrumentation, and precision sensor interfaces where conventional Zeners fail to meet noise and drift requirements.

FAQ

What is the nominal Zener voltage of the HZU4BLLTRF-E and how tightly is it specified?

The HZU4BLLTRF-E has a nominal Zener voltage of 3.9 V, with a guaranteed range of 3.7 V to 4.1 V measured at I_Z = 0.5 mA and T_A = 25°C. This ±0.2 V tolerance supports precise voltage referencing in analog circuits where absolute accuracy within 5% is required without trimming. The HZU4BLLTRF-E achieves this via epitaxial planar process control and laser-trimmed Zener junction design.

How does the noise performance of the HZU4BLLTRF-E compare to standard Zener diodes?

The HZU4BLLTRF-E delivers approximately one-third to one-tenth the noise voltage of the legacy HZU series, primarily due to optimized epitaxial layer doping and hard-knee junction geometry. Measured in the 0.1–10 Hz band, its ultra-low noise enables use in 24-bit delta-sigma ADC reference buffers where standard Zeners would contribute >1 µV_pp excess noise-directly improving effective resolution. This makes the HZU4BLLTRF-E uniquely suited among discrete Zeners for metrology-grade designs.

What is the temperature coefficient of the HZU4BLLTRF-E and why is it important for precision applications?

The HZU4BLLTRF-E has a typical temperature coefficient (γ_Z) of −0.03 mV/°C, roughly half that of the standard HZU series. This low drift ensures voltage variation remains under ±0.5 mV across a 0–70°C ambient range-critical for maintaining accuracy in unheated industrial sensors and portable test equipment. The coefficient is stabilized through epitaxial junction design and process tuning, making the HZU4BLLTRF-E suitable for applications where thermal compensation circuitry would otherwise be required.

Can the HZU4BLLTRF-E operate reliably at very low Zener currents such as 10 nA?

Yes-the HZU4BLLTRF-E exhibits semi-logarithmic V_Z-I_Z linearity from I_Z = 1 nA up to 1 mA, confirmed by characterization data in the official datasheet. At 10 nA, its Zener voltage remains within ±2% of the 0.5 mA value, enabling stable biasing in ultra-low-power sensor interfaces and nanoampere-scale current sources. This behavior is intrinsic to its hard-knee epitaxial planar structure and distinguishes it from conventional Zeners that become unstable below 100 µA.

What package type does the HZU4BLLTRF-E use and what are its key mechanical dimensions?

The HZU4BLLTRF-E uses the Ultra small Resin Package (URP), also known as SC-76A or JEITA code PTSP0002ZA-A. Key dimensions include: length l1 = 1.10–1.25 mm, width b = 1.55–1.70 mm, height A2 = 0.15–0.30 mm, and lead pitch e1 = 2.30 mm. Its 0.004 g mass and 0.8 × 1.25 mm footprint support high-density placement adjacent to precision analog ICs while minimizing thermal mass and parasitic capacitance-both essential for noise-sensitive reference routing.