Microchip Technology 1N5269B

Overview

1N5269B from Microsemi is a 500 mW glass axial-lead Zener diode in DO-35 (DO-204AH) package, rated for 87 V nominal Zener voltage at 1.4 mA test current, with ±5% tolerance, 2200 Ω maximum Zener impedance at knee current, and temperature coefficient of +0.099 %/°C. It regulates voltage in low-power reference and protection circuits across industrial and aerospace systems.

For engineers reviewing the 1N5269B datasheet, 1N5269B pinout, 1N5269B application, or 1N5269B equivalent, key selection criteria include its 87 V regulation point, 500 mW power rating at 25°C, DO-35 mechanical compatibility, cathode-band polarity marking, and suitability for stable voltage clamping in analog signal conditioning and power supply feedback paths.

Technical Context

The 1N5269B operates as a two-terminal reverse-biased voltage reference, leveraging avalanche breakdown at 87 V to maintain stable output under varying load and temperature conditions. Its 2200 Ω Zener impedance at IZK = 0.25 mA and +0.099 %/°C temperature coefficient indicate moderate regulation stability over temperature.

Designed for axial-leaded through-hole mounting, it features hermetically sealed glass construction, tin-lead or RoHS-compliant matte-tin plating, and operation from –65°C to +175°C. Forward voltage is ≤1.5 V at 200 mA, and it exhibits minimal capacitance per Figure 2 of the datasheet.

Key Specifications

Pinout & Package

DO-35 (DO-204AH) hermetically sealed glass axial-leaded package with cathode indicated by a single band; leads are tin-lead or RoHS-compliant matte-tin plated, solderable per MIL-STD-750 Method 2026.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5269C and MMBZ5269B, the 1N5269B offers the optimal balance of JEDEC-standardized axial-leaded reliability, 500 mW power headroom, and cost-effective ±5% tolerance for general-purpose high-voltage regulation-making it the default choice for through-hole industrial and aerospace designs where proven mechanical robustness is prioritized.

Availability

1N5269B is available at Aetrix Electronics and suitable for high-voltage power supply feedback, overvoltage protection clamping, and precision voltage reference applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 1N5269B 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 radiation-hardened components for aerospace, defense, and industrial markets.

The 1N52xxB series belongs to Microsemi's legacy DO-35 Zener diode product line, engineered for ruggedized voltage regulation in mission-critical systems where long-term stability, extreme temperature operation, and JEDEC compliance are mandatory.

FAQ

What is the nominal Zener voltage and tolerance of the 1N5269B?

The 1N5269B has a nominal Zener voltage of 87 V at 1.4 mA test current, with a guaranteed tolerance of ±5% (denoted by the "B" suffix). This means its actual breakdown voltage falls between 82.65 V and 91.35 V at 25°C, enabling predictable design margins in high-voltage regulation circuits where the 1N5269B serves as the primary reference element.

What package type and mounting style does the 1N5269B use?

The 1N5269B uses the DO-35 (also designated DO-204AH) hermetically sealed glass axial-leaded package. It is designed for through-hole mounting with 3/8″ (10 mm) minimum lead length from the body to ensure proper thermal dissipation. The cathode is marked by a single band on the glass body, and the leads are tin-lead or RoHS-compliant matte-tin plated per MIL-STD-750.

What is the maximum power dissipation and thermal derating behavior of the 1N5269B?

The 1N5269B is rated for 500 mW power dissipation at 25°C ambient or lead temperature. Derating begins linearly above 25°C, reaching zero power at 175°C per the published curve (Figure 1). Thermal resistance is 250°C/W junction-to-lead (at 3/8″ lead length) or 310°C/W junction-to-ambient on FR4 board - critical parameters for thermal design when using the 1N5269B in enclosed or high-temperature environments.

How does the temperature coefficient of the 1N5269B affect its performance?

The 1N5269B has a positive temperature coefficient of +0.099 %/°C, meaning its Zener voltage increases by approximately 86 mV per °C rise in junction temperature. This behavior is confirmed for devices rated 1N5243A/B through 1N5281A/B under specified test conditions (IZT at rated value, T1 = 25°C, T2 = 125°C), and must be factored into precision 1N5269B applications operating across wide temperature ranges.

Is the 1N5269B suitable for aerospace or high-reliability applications?

Yes - the 1N5269B is JEDEC-registered and supports military screening levels (JAN, JANTX, JANTXV, JANS) when ordered with appropriate prefixes and the "-1" suffix. Its inherent radiation hardness (per MicroNote 050), ESD insensitivity (MIL-STD-750 Method 1020), and –65°C to +175°C operating range make it qualified for aerospace, defense, and oilfield electronics where the 1N5269B provides trusted voltage regulation under extreme stress conditions.