Microchip Technology 1N5271B/TR

Overview

1N5271B/TR from Microsemi is a 100 V, ±5% tolerance, 500 mW glass axial-lead Zener diode in DO-35 (DO-204AH) package, rated for 1.3 mA test current and 2600 Ω dynamic impedance at 0.25 mA, operating across –65°C to +175°C for voltage regulation in power supply reference and overvoltage protection circuits.

For engineers reviewing the 1N5271B/TR datasheet, 1N5271B/TR pinout, 1N5271B/TR application, or 1N5271B/TR equivalent, key selection criteria include its 100 V nominal Zener voltage, tight ±5% tolerance (B suffix), low temperature coefficient of +0.110 %/°C, and suitability for high-temperature industrial and aerospace environments requiring stable regulation under wide thermal and current variation.

Technical Context

This Zener diode operates in reverse breakdown mode with cathode band indicating polarity, requiring the banded end to be held positive relative to the anode for regulation. Its 2600 Ω Zener impedance at IZK = 0.25 mA and 500 mW power rating at 25°C define its precision and thermal limits.

The device exhibits a +0.110 %/°C temperature coefficient above 6.8 V, measured between 25°C and 125°C at rated IZT, and maintains ≤0.1 μA reverse leakage at VR = 72 V - confirming stable regulation across extended temperature ranges without external compensation.

Key Specifications

Pinout & Package

Hermetically sealed DO-35 (DO-204AH) glass axial-leaded package with cathode indicated by a single black 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 1N5271B/TR, the non-taped 1N5271B offers identical performance at lower unit cost for hand-soldered prototypes, while MMBZ5271B trades package miniaturization for 30% lower power headroom - making 1N5271B/TR optimal for through-hole production with automated assembly and full 500 mW capability.

Availability

1N5271B/TR is available at Aetrix Electronics and suitable for industrial power supplies, aerospace clamping circuits, and downhole sensor biasing requiring stable component supply with guaranteed long-term continuity.

Supply support for 1N5271B/TR 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 and mixed-signal components for aerospace, defense, and industrial markets.

The 1N52xxB series was designed specifically for ruggedized voltage regulation in mission-critical systems where extended temperature operation, radiation tolerance, and JEDEC-standard interchangeability are mandatory.

FAQ

What is the Zener voltage tolerance of the 1N5271B/TR?

The 1N5271B/TR has a nominal Zener voltage of 100 V with a guaranteed tolerance of ±5%, as indicated by the "B" suffix per JEDEC specification. This tolerance applies at 25°C with 1.3 mA test current and remains valid across the full operating temperature range of –65°C to +175°C per Microsemi's published characterization data.

Does the 1N5271B/TR require heatsinking in typical applications?

No, the 1N5271B/TR does not require external heatsinking when operated at or below its 500 mW rating at 25°C ambient. Its thermal resistance is 250°C/W junction-to-lead (at 10 mm lead length), allowing direct mounting on FR4 PCBs with standard copper pads. Derating begins linearly above 50°C lead temperature, reaching zero power at 175°C.

How is polarity marked on the 1N5271B/TR?

The 1N5271B/TR uses a single black cathode band on the glass body to indicate polarity. For proper Zener regulation, the banded (cathode) end must be held at a more positive potential than the unbanded (anode) end. This marking conforms to JEDEC DO-35 standards and is visible under standard optical inspection.

Is the 1N5271B/TR suitable for high-reliability aerospace applications?

Yes, the 1N5271B/TR is qualified for aerospace use: it meets MIL-PRF-19500 screening levels when ordered with appropriate prefixes (e.g., MV for JANTXV), exhibits inherent radiation hardness per MicroNote 050, and operates reliably from –65°C to +175°C - all confirmed in Microsemi's official documentation and test reports.

What is the maximum reverse leakage current for the 1N5271B/TR?

The maximum reverse leakage current (I_R) for the 1N5271B/TR is 0.1 μA when tested at 72 V (0.72 × V_Z), per the Electrical Characteristics table on page 1 of the Microsemi datasheet. This value is guaranteed across the full temperature range and confirms minimal standby current in high-impedance bias networks.