Microchip Technology 1N982A

Overview

1N982A from Microsemi is a silicon 500 mW axial-lead Zener diode with nominal Zener voltage 75 V, ±10% tolerance (A suffix), 1.7 mA Zener test current, 270 Ω dynamic impedance at I_ZT, and maximum reverse leakage of 5 μA at 56 V. It operates in voltage regulation and reference applications across industrial power supplies and analog signal conditioning circuits.

For engineers reviewing the 1N982A datasheet, 1N982A pinout, 1N982A application, or 1N982A equivalent, key selection criteria include its DO-35 glass package, cathode-band polarity marking, -65°C to +175°C operating temperature range, and thermal resistance of 250°C/W junction-to-lead (3/8" lead length).

Technical Context

The 1N982A functions as a two-terminal voltage reference device operating in reverse breakdown mode. Its Zener voltage is stabilized by avalanche mechanism above ~6 V, with temperature coefficient +0.098%/°C and minimal capacitance per Figure 3.

It requires external current limiting via series resistor and exhibits stable regulation over 1.7 mA to 5.0 mA operating current range. The device is nonsensitive to ESD per MIL-STD-750 Method 1020 and inherently radiation-hardened per MicroNote 050.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N982A, the 1N982B offers improved voltage accuracy at no change in thermal or electrical stress margins, while 1N982C further reduces tolerance to ±2%-both retain identical pinout, package, and temperature performance, enabling direct substitution where board layout permits.

Availability

1N982A is available at Aetrix Electronics and suitable for industrial power supply regulation, automotive sensor reference, test equipment voltage standards, and avionics overvoltage protection requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 1N982A 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, mixed-signal, and RF solutions for aerospace, defense, and industrial markets.

The 1N957B–1N992B Zener series was designed for ruggedized voltage regulation in mission-critical systems where extended temperature operation, radiation tolerance, and hermetic packaging are mandatory.

FAQ

What is the Zener voltage tolerance for 1N982A?

The 1N982A has a nominal Zener voltage of 75 V with ±10% tolerance, as indicated by the "A" suffix per Microsemi's JEDEC-registered naming convention. This means the actual measured V_Z at I_ZT = 1.7 mA falls between 67.5 V and 82.5 V at 25°C. The 1N982A datasheet specifies this tolerance in Note 1 on Page 2.

What is the maximum power dissipation for 1N982A at room temperature?

The 1N982A is rated for 500 mW steady-state power dissipation when lead temperature (T_L) is maintained at or below 50°C, measured 3/8 inch from the body. At ambient temperature (T_A) < 25°C on FR4 board, derated power is 480 mW. Thermal resistance is 250°C/W junction-to-lead, per Maximum Ratings table on Page 1.

How is polarity marked on the 1N982A package?

The 1N982A uses standard DO-35 axial-lead glass packaging with cathode polarity indicated by a visible band near one end of the glass body. During Zener operation, the banded end must be held at higher potential relative to the non-banded (anode) end. Forward voltage is ≤1.1 V at 200 mA, confirming standard silicon diode conduction direction.

Is the 1N982A RoHS compliant?

The base 1N982A is not RoHS compliant by default. RoHS compliance requires the "e3" suffix (e.g., 1N982Ae3), which denotes annealed matte-tin plating per Microsemi's specification. Standard 1N982A uses traditional tin-lead (Sn/Pb) plating solderable per MIL-STD-750 Method 2026.

What is the temperature coefficient of the 1N982A?

The 1N982A has a Zener voltage temperature coefficient of +0.098%/°C, meaning its regulated voltage increases by approximately 0.0735 V per °C rise in junction temperature. This value is confirmed in the Electrical Characteristics table on Page 2 and correlates with its 75 V nominal rating in the +0.098%/°C column.