Microchip Technology 1N986A

Overview

1N986A from Microsemi is a silicon 500 mW axial-lead Zener diode in DO-35 (DO-204AH) package, rated for 110 V nominal Zener voltage with ±10% tolerance (A suffix), 1.1 mA maximum reverse leakage at 83.6 V, and +0.11 %/°C temperature coefficient. It operates from –65°C to +175°C and is used for precision voltage reference and overvoltage protection in industrial power supplies.

For engineers reviewing the 1N986A datasheet, 1N986A pinout, 1N986A application, or 1N986A equivalent, key selection factors include its 110 V Zener voltage, ±10% tolerance, 0.5 W power rating at TL < 50°C, DO-35 mechanical form factor, and cathode-band polarity marking - all critical for legacy analog regulator and clamp circuit design.

Technical Context

The 1N986A functions as a two-terminal voltage-reference device operating in reverse breakdown, with Zener test current IZT = 1.1 mA and dynamic impedance ZZT = 750 Ω at IZT. Its thermal resistance is 250 °C/W junction-to-lead (3/8″ lead length) and 310 °C/W junction-to-ambient on FR4 board.

It exhibits a positive temperature coefficient of +0.11 %/°C and maximum reverse leakage IR = 5 μA at VR = 83.6 V. Forward voltage is ≤1.3 V at 200 mA, and it is nonsensitive to ESD per MIL-STD-750 Method 1020.

Key Specifications

Pinout & Package

Package: DO-35 (DO-204AH), hermetically sealed glass axial-leaded case with cathode indicated by colored band. Tin-lead or RoHS-compliant matte-tin plating, weight 0.2 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N986A, the 1N986B offers tighter voltage control at the expense of higher unit cost, while 1N986C further reduces tolerance for high-accuracy instrumentation - both retain identical thermal, mechanical, and surge ratings, enabling drop-in replacement where board space and mounting constraints match.

Availability

1N986A is available at Aetrix Electronics and suitable for industrial power supply regulation, telecom overvoltage clamping, legacy instrumentation reference, and high-voltage sensor biasing requiring stable component supply and long-term obsolescence management.

Supply support for 1N986A 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 aerospace, defense, and industrial markets.

The 1N957B–1N992B series was designed specifically for legacy-compatible, high-temperature-stable Zener regulation in mission-critical analog systems where DO-35 form factor and JEDEC registration ensure interchangeability and long-lifecycle support.

FAQ

What is the Zener voltage tolerance for 1N986A?

The 1N986A has a nominal Zener voltage of 110 V with ±10% tolerance, as indicated by the "A" suffix per Microsemi's documentation. This means the actual measured VZ at IZT = 1.1 mA falls between 99 V and 121 V under standard test conditions (25°C, 20-second stabilization). The tolerance is fixed by manufacturing binning and cannot be adjusted in-circuit.

Can 1N986A be used in surface-mount designs?

No, the 1N986A is exclusively offered in the through-hole DO-35 (DO-204AH) axial-leaded package. For surface-mount equivalents, Microsemi lists MLL986B in DO-213AA (MELF) package - but that part uses the "B" (±5%) suffix and requires layout redesign. The 1N986A itself has no SMT variant.

What is the maximum reverse leakage current for 1N986A?

The 1N986A specifies a maximum reverse leakage current (IR) of 5 μA at VR = 83.6 V (76% of nominal VZ), per the Electrical Characteristics table on page 2 of the Microsemi datasheet. This value is measured at 25°C and remains valid up to +125°C, with typical leakage increasing less than 10× over the full –65°C to +175°C operating range.

Does 1N986A require heatsinking in normal operation?

No heatsink is required for the 1N986A at ambient temperatures below 50°C and power dissipation ≤0.5 W. Its thermal resistance is 250 °C/W junction-to-lead (3/8″ from body), so at 0.4 W dissipation and 50°C lead temperature, junction temperature stays at 150°C - within the +175°C absolute maximum. Derating per Figure 1 applies above 50°C lead temp.

Is 1N986A RoHS compliant?

The base 1N986A is not RoHS compliant; however, Microsemi offers an RoHS-compliant version designated 1N986Ae3, where the "e3" suffix indicates annealed matte-tin plating and lead-free construction per JEDEC J-STD-609. This variant maintains identical electrical and thermal specifications and is fully interchangeable in assembly except for solder profile adjustments.