Microchip Technology CDLL4116

Overview

CDLL4116 from Microsemi is a hermetically sealed, surface-mount silicon Zener diode in DO-213AA (MELF/LL34) package, rated for 24 V nominal Zener voltage at 250 µA test current, 150 Ω maximum Zener impedance, 18.25 V minimum reverse voltage, and 16 mA maximum Zener current - used for precision voltage reference and overvoltage protection in aerospace-grade power regulation circuits.

For engineers reviewing the CDLL4116 datasheet, CDLL4116 pinout, CDLL4116 application, or CDLL4116 equivalent, key selection factors include its ±5% Zener tolerance, -65°C to +175°C junction temperature range, 500 mW power dissipation at 125°C, low-leakage performance (<0.01 µA at 18.25 V), and hermetic glass construction for high-reliability mil-aero environments.

Technical Context

The CDLL4116 operates as a two-terminal voltage reference device with cathode-banded polarity, requiring reverse-bias connection to maintain stable breakdown conduction. Its metallurgically bonded junction ensures long-term stability under thermal cycling and radiation exposure typical in space and defense systems.

Designed per MIL-PRF-19500/435 Class JANTXV, it supports low-current regulation down to 250 µA and exhibits predictable Zener impedance behavior across 1–100 mA operating range, with thermal resistance of 100 °C/W at zero lead length and axial coefficient of expansion matched to ceramic substrates.

Key Specifications

Pinout & Package

DO-213AA (MELF/LL34) hermetically sealed glass package with axial leads; banded end denotes cathode terminal. No discrete pins - bidirectional axial terminals require orientation-aware PCB placement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CDLL4116, 1N4116UR-1 offers identical electrical specs with enhanced military traceability, while BZX84-C24 trades hermetic reliability and temperature range for lower cost and smaller footprint in benign environments.

Availability

CDLL4116 is available at Aetrix Electronics and suitable for avionics power monitoring, satellite bus voltage reference, and downhole tool regulation requiring stable component supply across extended temperature and high-reliability environments.

Supply support for CDLL4116 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

Microsemi (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog and mixed-signal components for aerospace, defense, and industrial markets.

The CDLL4099–CDLL4135 series was designed specifically to meet MIL-PRF-19500/435 requirements for hermetic, surface-mount Zener references in mission-critical power and sensing systems.

FAQ

What is the Zener voltage tolerance for CDLL4116?

The CDLL4116 has a nominal Zener voltage of 24 V with a tolerance of ±5%, as specified in Note 1 of the official Microsemi datasheet. This tolerance applies under thermal equilibrium at 25°C ± 3°C and does not include tighter-tolerance variants (e.g., "C" or "D" suffixes). The CDLL4116 itself carries no suffix, confirming its standard ±5% grade.

Is CDLL4116 suitable for space applications?

Yes, CDLL4116 meets MIL-PRF-19500/435 Class JANTXV requirements, including radiation hardness assurance, hermetic glass packaging, and extended temperature operation (-65°C to +175°C), making it qualified for use in low-earth orbit satellite power systems where long-term parametric stability is critical. The CDLL4116 is routinely selected for bus voltage supervision in CubeSat platforms.

What is the maximum reverse leakage current for CDLL4116?

The CDLL4116 exhibits a maximum reverse leakage current of 0.01 µA at 18.25 V (75% of nominal Zener voltage), per the Electrical Characteristics table. This ultra-low leakage supports energy-efficient operation in battery-powered telemetry nodes and ensures minimal error contribution in high-impedance reference circuits using the CDLL4116.

Does CDLL4116 require heatsinking in standard operation?

No, CDLL4116 does not require external heatsinking under typical operating conditions. With a thermal resistance of 100 °C/W at L = 0 inch and rated 500 mW dissipation at 125°C end-cap temperature, the CDLL4116 remains within safe junction limits up to ~16 mA at ambient temperatures below 105°C - well within its 16 mA I_ZM rating. The CDLL4116's MELF geometry naturally aids convective cooling.

How does CDLL4116 differ from CDLL4115 and CDLL4117?

CDLL4116 is electrically distinct from adjacent family members: CDLL4115 is rated for 22 V Zener voltage and CDLL4117 for 25 V, each with identical test current (250 µA), impedance (150 Ω), and leakage (<0.01 µA) specifications. The CDLL4116 serves as the dedicated 24 V node in this tightly spaced Zener ladder, enabling precise mid-range voltage referencing between those values without interpolation.