Microchip Technology 1N5258A

Overview

1N5258A from Microsemi is a 36 V, ±10% tolerance, 500 mW glass axial-lead Zener diode in DO-35 (DO-204AH) package, rated for 3.4 mA test current, 70 Ω dynamic impedance at IZK, and operating from –65°C to +175°C. It serves as a precision voltage reference or shunt regulator in low-power analog circuits, power supply feedback paths, and overvoltage protection.

For engineers reviewing the 1N5258A datasheet, 1N5258A pinout, 1N5258A application, or 1N5258A equivalent, key selection criteria include its 36 V nominal Zener voltage, ±10% tolerance (A suffix), 70 Ω Zener impedance at 0.25 mA, temperature coefficient of +0.093 %/°C, and DO-35 mechanical compatibility with axial-leaded PCB mounting.

Technical Context

This discrete Zener diode operates in reverse breakdown mode with cathode band marking polarity. Its regulation is defined at IZT = 3.4 mA and characterized across –65°C to +175°C ambient, with thermal resistance of 250 °C/W junction-to-lead (3/8″ lead length).

It exhibits minimal capacitance per Figure 2, is nonsensitive to ESD per MIL-STD-750 Method 1020, and is inherently radiation-hardened per MicroNote 050 - features critical for aerospace and industrial control applications requiring long-term stability under harsh conditions.

Key Specifications

Pinout & Package

DO-35 (DO-204AH) hermetically sealed glass axial-leaded package with tin-lead or RoHS-compliant matte-tin plating; cathode identified by single black band on glass body.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5258A, 1N4738A offers higher power and tighter tolerance at a different voltage, while MMBZ5258ELT1G provides identical Zener voltage in a compact SMT form - neither is pin-compatible, but both serve overlapping regulation roles with trade-offs in power, size, and thermal management.

Availability

1N5258A is available at Aetrix Electronics and suitable for overvoltage protection, precision reference generation, and feedback regulation in industrial controls, aerospace subsystems, and test equipment requiring stable component supply and long-lifecycle support.

Supply support for 1N5258A 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, radiation-hardened, and high-voltage analog components for defense, aerospace, and industrial markets.

The 1N52xxA/B series was designed for robust, low-cost voltage regulation in mission-critical analog circuits where extended temperature operation, ESD immunity, and JEDEC-standard mechanical compatibility are mandatory.

FAQ

What is the nominal Zener voltage and tolerance of the 1N5258A?

The 1N5258A has a nominal Zener voltage of 36 V with a tolerance of ±10%, as indicated by the "A" suffix per Microsemi's documentation. This tolerance applies under standard test conditions at 25°C with IZT = 3.4 mA. The 1N5258A is not rated for tighter tolerances like ±5% (B suffix) or ±1% (D suffix); those require different part numbers in the same family.

What package type and marking does the 1N5258A use?

The 1N5258A uses the DO-35 (DO-204AH) glass axial-leaded package with hermetic sealing and tin-lead or RoHS-compliant matte-tin plating. It is marked with the full part number "1N5258A" on the glass body, and polarity is indicated by a single black cathode band at the banded end - the 1N5258A must be reverse-biased (cathode positive) to operate in Zener regulation mode.

What is the Zener impedance and test condition for the 1N5258A?

The 1N5258A has a maximum Zener impedance (ZZK) of 70 Ω measured at IZK = 0.25 mA, per the Electrical Characteristics table. This value reflects dynamic impedance near the knee of the breakdown curve and is critical for assessing regulation stability under light-load or transient conditions. The 1N5258A does not specify ZZT (impedance at IZT) in the provided data sheet.

Does the 1N5258A have radiation hardness or ESD immunity specifications?

Yes - the 1N5258A is inherently radiation-hardened per MicroNote 050 and is nonsensitive to ESD per MIL-STD-750 Method 1020. These characteristics are explicitly documented in the Features section of the Microsemi datasheet and apply directly to the 1N5258A as a member of the 1N5221–1N5281B family. No additional screening or suffix is required to obtain these properties.

What is the maximum power dissipation and thermal resistance of the 1N5258A?

The 1N5258A has a maximum steady-state power dissipation of 500 mW at 25°C ambient, with thermal resistance of 250 °C/W junction-to-lead (measured at 3/8″ lead length from body). When mounted on an FR4 PCB with specified copper pads, its junction-to-ambient thermal resistance rises to 310 °C/W, reducing usable power to 480 mW at TA < 25°C - all values confirmed in the Maximum Ratings section for the 1N5258A.