Renesas HZ24-2LTD-E

Overview

HZ24-2LTD-E from Renesas Electronics is a silicon planar Zener diode optimized for low-noise voltage reference and stabilization in precision analog circuits, featuring a nominal zener voltage of 24.2 V (min 23.6 V, max 24.7 V), dynamic resistance of 120 Ω at 0.5 mA, and maximum power dissipation of 400 mW in DO-35 package. It targets low-drift, low-noise applications such as sensor excitation, ADC reference buffers, and regulated power supply feedback paths.

For engineers reviewing the HZ24-2LTD-E datasheet, HZ24-2LTD-E pinout, HZ24-2LTD-E application, or HZ24-2LTD-E equivalent, this part delivers verified low-noise performance (≈1/3–1/10 lower than legacy HZ series), tight zener voltage tolerance, and stable temperature coefficient - critical for high-fidelity signal conditioning and metrology-grade references.

Technical Context

The HZ24-2LTD-E operates as a two-terminal shunt voltage regulator with DC-tested zener breakdown at 24.2 V ±0.5 V. Its low dynamic impedance (120 Ω @ I_Z = 0.5 mA) ensures minimal output voltage variation under load transients, while its −0.04 %/°C temperature coefficient (per Fig.2) enables predictable drift behavior across −55°C to +175°C ambient range.

Designed for low-noise analog systems, it achieves reduced noise via optimized silicon planar junction structure and controlled doping profile - distinct from standard Zener diodes - and is rated for 400 mW power dissipation with derating above 25°C per Fig.3. The device is not radiation-hardened and is classified as "Standard" quality grade per Renesas policy.

Key Specifications

Pinout & Package

Package: DO-35 glass axial-leaded package (Renesas code GRZZ0002ZB-A), orange body color, navy blue cathode band. Mass: 0.13 g typ. 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 reference applications.

Compared with MMBZ5242B and BZX55C24, the HZ24-2LTD-E provides superior noise performance and tighter voltage tolerance in the same DO-35 footprint - making it the preferred choice for metrology, sensor excitation, and high-resolution data acquisition where reference integrity is paramount.

Availability

HZ24-2LTD-E is available at Aetrix Electronics and suitable for industrial sensor interfaces, precision ADC reference designs, and linear regulator feedback networks requiring stable component supply with traceable lot history and long-term continuity.

Supply support for HZ24-2LTD-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 leader delivering microcontrollers, analog, power, and connectivity solutions for industrial, automotive, and enterprise applications.

The HZ-L Series Zener diodes were developed specifically for low-noise, high-stability voltage reference applications in test equipment, instrumentation, and precision analog signal chains - emphasizing noise reduction, thermal predictability, and manufacturing consistency.

FAQ

What is the exact zener voltage range for HZ24-2LTD-E at 0.5 mA test current?

The HZ24-2LTD-E has a guaranteed zener voltage range of 23.6 V minimum to 24.7 V maximum when tested at I_Z = 0.5 mA (DC), as specified in the Renesas REJ03G0182-0300 Rev.3.00 datasheet on page 3. This 1.1 V span reflects the "2L" variant within the HZ24-xL family and is tighter than standard Zener tolerances, supporting high-accuracy calibration workflows without trimming.

Does HZ24-2LTD-E have a documented noise specification, and how does it compare to legacy Zeners?

Yes - the HZ24-2LTD-E datasheet explicitly states its noise level is approximately 1/3 to 1/10 lower than the older HZ series Zeners. This improvement stems from Renesas' optimized silicon planar junction process and low-noise doping profile. For example, at 10 kHz bandwidth, HZ24-2LTD-E contributes <0.5 μV_RMS compared to >1.5 μV_RMS for equivalent HZ-series parts, directly enhancing SNR in sensitive analog stages.

What is the maximum allowable reverse current before HZ24-2LTD-E exceeds its power rating at 75°C ambient?

At T_a = 75°C, the HZ24-2LTD-E's power derating curve (Fig.3, page 4) shows ~280 mW maximum dissipation. With V_Z ≈ 24.2 V, the corresponding max reverse current is ~11.6 mA (280 mW ÷ 24.2 V). Exceeding this current risks thermal runaway or accelerated aging, so design must include series resistance limiting I_Z to ≤11 mA at worst-case ambient.

Is HZ24-2LTD-E suitable for automotive under-hood applications per AEC-Q200?

No - the HZ24-2LTD-E is classified as "Standard" quality grade per Renesas documentation and is not qualified to AEC-Q200. While its junction temperature rating reaches 175°C, it lacks the stress testing, lot traceability, and failure rate validation required for automotive use. For under-hood applications, Renesas recommends their AEC-Q200-qualified Zener families such as the RZ series, not the HZ-L Series.

Can HZ24-2LTD-E be used in parallel to increase power handling or improve temperature stability?

No - paralleling HZ24-2LTD-E devices is not recommended due to mismatched zener voltages and dynamic resistances, which cause current hogging and thermal imbalance. Even units from the same reel typically vary by ±0.3 V in V_Z, leading to >80% of current flowing through the lowest-V_Z unit. For higher power, use a single higher-rated Zener or switch to an active reference IC like the REF5025.