Microchip Technology 1N4566

Overview

1N4566 from Microsemi is a 6.4 V temperature-compensated Zener reference diode in DO-7 (DO-204AA) glass axial package, rated for 0.5 mA test current, ±0.005 %/°C temperature coefficient, 200 Ω dynamic impedance, and operation from –65 °C to +175 °C. It delivers high-stability voltage reference for precision analog circuits requiring minimal drift over temperature.

For engineers reviewing the 1N4566 datasheet, 1N4566 pinout, 1N4566 application, or 1N4566 equivalent, key selection criteria include its ultra-low TC (0.005 %/°C), tight 6.4 V nominal tolerance, hermetic DO-7 packaging, military-grade qualification path (JAN/JANTX/JANTXV with -1 suffix), and suitability for high-reliability instrumentation and aerospace power supply references.

Technical Context

The 1N4566 uses internal metallurgical bonding to achieve stable Zener breakdown at precisely 6.4 V with minimized thermal hysteresis. Its temperature compensation architecture reduces voltage drift across –65 °C to +175 °C operating range, enabling use without external trimming in critical analog subsystems.

Rated for 500 mW maximum power dissipation at 25 °C lead temperature, it operates optimally below 30 mW (IZT = 0.5 mA), ensuring low self-heating and long-term stability. Reverse leakage remains ≤2.0 µA at 3 V, supporting low-noise biasing in high-impedance reference nodes.

Key Specifications

Pinout & Package

DO-7 (DO-204AA) hermetically sealed glass axial package with cathode band marking; leads are tin-lead plated per MIL-STD-750 Method 2026. Polarity requires banded end to be positive relative to unbanded end during forward-biased reference operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4566, the 1N4566A improves initial accuracy without altering thermal behavior, while 1N4567 further reduces temperature drift at the expense of higher cost and less common availability-making 1N4566 the optimal balance of stability, ruggedness, and procurement flexibility for high-reliability embedded systems.

Availability

1N4566 is available at Aetrix Electronics and suitable for high-reliability instrumentation, aerospace power management, and downhole sensor conditioning requiring stable component supply across extended temperature and long lifecycle programs.

Supply support for 1N4566 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, RF, and radiation-hardened components for defense, aerospace, and industrial markets.

The 1N4565–1N4584A series was engineered specifically for mission-critical voltage reference applications demanding hermetic sealing, extreme temperature resilience, and MIL-qualified variants-targeting avionics, space systems, and energy exploration electronics.

FAQ

What is the nominal Zener voltage and tolerance of the 1N4566?

The 1N4566 has a nominal Zener voltage of 6.4 V with a standard tolerance of ±5%. Tighter tolerances (e.g., ±1%, ±2%) are available via suffix notation like 1N4566A-1%, but the base 1N4566 part adheres to the ±5% specification per JEDEC registration and Microsemi's REV B datasheet.

What is the temperature coefficient of the 1N4566 and how is it measured?

The 1N4566 exhibits a temperature coefficient of ±0.005 %/°C, measured over the 0 °C to +75 °C range per the Electrical Characteristics table. This value reflects the rate of Zener voltage change per degree Celsius and is verified at IZT = 0.5 mA, ensuring minimal drift in precision reference applications.

Can the 1N4566 be used in military or aerospace applications?

Yes-the 1N4566 qualifies for military use when ordered with appropriate prefixes and suffixes: JAN1N4566-1, JANTX1N4566-1, or JANTXV1N4566-1 meet MIL-PRF-19500/452 requirements. The base 1N4566 is commercial-grade, but the -1 suffix and prefix enable full qualification for defense and space programs.

What package type does the 1N4566 use and what are its key mechanical features?

The 1N4566 uses the DO-7 (also designated DO-204AA) hermetically sealed glass axial package. Key features include tin-lead solderable leads per MIL-STD-750 Method 2026, cathode band marking, 0.2 g weight, and compatibility with 260 °C soldering for 10 seconds-enabling robust mounting in high-reliability assemblies.

How does the 1N4566 differ from the 1N4565 in terms of temperature stability?

The 1N4566 offers ±0.005 %/°C temperature coefficient versus ±0.01 %/°C for the 1N4565-halving the thermal drift rate. Both share identical 6.4 V nominal voltage, 0.5 mA IZT, and DO-7 packaging, making the 1N4566 the preferred choice when tighter thermal stability is required without changing bias or layout.