1N4958

Overview

The Microchip Technology 1N4958 is a military-qualified, voidless hermetically sealed glass Zener diode designed for high-reliability applications. It features a nominal Zener voltage of 10 V with a standard tolerance of ±5%. The device operates within a temperature range of -65°C to +175°C and dissipates up to 5 Watts at a lead temperature of 65°C. Electrical characteristics include a maximum dynamic impedance of 2.0 Ohms at the test current of 125 mA, a maximum reverse leakage current of 25 µA at 7.6 V, and a forward voltage of 1.50 V at 1.0 A.

Feature Summary

• Hermetically sealed in voidless hard glass with tungsten slugs
• Internal Category I metallurgical bonds for robust construction
• Triple-layer passivation for enhanced durability
• Inherently radiation hard

Applications

• High-reliability aerospace systems
• Military-grade voltage regulation circuits
• Critical power supply protection
• Harsh environment electronics

Procurement Notes

Verify that the specific part number matches the required military qualification level (e.g., JAN, JANTX) as suffixes define the reliability grade. Confirm compliance with MIL-PRF-19500/356 standards. Ensure the ordering suffix aligns with the desired tolerance and package configuration. Check for RoHS status if applicable to your assembly process.

Selection Notes

Select this component when a 5 Watt axial-lead Zener diode with extreme temperature stability (-65°C to +175°C) is required. The 1N4958 provides a precise 10 V reference with low dynamic impedance. Consider the hermetic seal and radiation hardness for environments where standard commercial parts would fail. Verify thermal derating requirements based on your specific mounting conditions.

Part Context

This device belongs to the 1N4954 through 1N4996 series of 5 Watt Zener Voltage Regulators manufactured by Microsemi (now Microchip Technology). The series is widely recognized for its military qualification under MIL-PRF-19500/356. These regulators are available in various voltage selections from 3.3 V to 390 V, offering flexibility for diverse high-power voltage regulation needs in demanding applications.

Replacement Considerations

Direct replacements must match the 1N4958's 10 V Zener voltage, 5 W power rating, and hermetic glass package. Equivalent parts should meet or exceed the MIL-PRF-19500/356 specification. Verify that any substitute maintains the same axial lead configuration and thermal resistance characteristics to ensure compatibility with existing board layouts and heat dissipation designs.