Microchip Technology 1N965A

Overview

1N965A from Microsemi is a silicon 500 mW axial-leaded Zener diode in DO-35 (DO-204AH) package, rated for 15 V nominal Zener voltage with ±10% tolerance, 8.5 mA Zener test current, and 700 Ω maximum Zener impedance at I_ZT. It operates across –65°C to +175°C and is used for precision voltage reference and overvoltage protection in low-power analog circuits.

For engineers reviewing the 1N965A datasheet, 1N965A pinout, 1N965A application, or 1N965A equivalent, key selection criteria include its 15 V regulation point, ±10% tolerance (A suffix), 0.5 W power rating at 50°C lead temperature, DO-35 mechanical compatibility, and cathode-band polarity marking - all critical for legacy industrial power supply and sensor biasing designs.

Technical Context

The 1N965A functions as a two-terminal voltage reference device operating in reverse breakdown mode, with regulation established by controlled avalanche and Zener mechanisms depending on voltage level. Its 15 V nominal Zener voltage places it in the mixed-mechanism region where temperature coefficient is +0.082 %/°C - a stable positive drift suitable for compensated reference designs.

It exhibits 0.25 mA maximum reverse leakage at 11.4 V (75% of V_Z), 25 mA maximum DC Zener current (I_ZM), and 130 mA maximum surge current for 1/120 sec pulses. Thermal resistance is 250 °C/W junction-to-lead at 3/8″ lead length, enabling reliable operation in high-temperature environments without forced cooling.

Key Specifications

Pinout & Package

Package: DO-35 (DO-204AH), hermetically sealed axial-leaded glass body, 0.2 g weight, cathode indicated by single band. Tin-lead or RoHS-compliant matte-tin plating per MIL-STD-750 Method 2026.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N965A, the 1N965B offers improved voltage accuracy at identical form factor and thermal behavior, while the MMBZ5245B trades power rating and mounting style for miniaturization - making 1N965A optimal for cost-sensitive, through-hole, high-reliability legacy systems.

Availability

1N965A is available at Aetrix Electronics and suitable for industrial power supplies, sensor conditioning circuits, overvoltage protection networks, and legacy equipment repair requiring stable component supply and long-term obsolescence management.

Supply support for 1N965A 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 ruggedized, high-temperature voltage regulation in mission-critical systems where long-term parametric stability and JEDEC-standard compliance are mandatory.

FAQ

What is the Zener voltage tolerance of the 1N965A?

The 1N965A has a nominal Zener voltage of 15 V with ±10% tolerance, as indicated by the "A" suffix per Microsemi's documentation. This means the actual measured V_Z at 8.5 mA test current falls between 13.5 V and 16.5 V at 25°C. The tolerance is wider than the B-suffix variant (±5%) but provides cost and availability advantages for non-critical regulation tasks.

Can the 1N965A be used in high-temperature environments?

Yes, the 1N965A is rated for operation from –65°C to +175°C, with thermal resistance of 250 °C/W junction-to-lead at 3/8″ lead length. Its hermetically sealed DO-35 glass package and silicon construction enable reliable performance in downhole tools, engine control units, and avionics where extended temperature range is essential - confirmed in Microsemi's published maximum ratings table.

What does the "A" suffix mean in 1N965A?

The "A" suffix in 1N965A denotes ±10% Zener voltage tolerance, per Microsemi's official documentation. Other suffixes include B (±5%), C (±2%), D (±1%), and no suffix (±20%). This suffix system is JEDEC-registered and applies uniformly across the 1N957B–1N992B series, allowing consistent specification interpretation across the family.

Is the 1N965A RoHS compliant?

The base 1N965A is not inherently RoHS compliant; RoHS compliance requires the "e3" suffix (e.g., 1N965Ae3). Standard 1N965A uses tin-lead plating, while the e3 variant substitutes annealed matte-tin per Microsemi's packaging specifications. Always verify suffix and ordering code to ensure regulatory alignment for your target market.

What is the maximum surge current rating for the 1N965A?

The 1N965A has a maximum surge current (I_ZSM) rating of 130 mA for a 1/120 second duration square-wave or half-sine pulse, as specified in Microsemi's Electrical Characteristics table. This value reflects short-duration transient energy absorption capability and is distinct from continuous DC Zener current (I_ZM = 25 mA).