1N4479

Single Zener Diodes Overview

The Microchip Technology 1N4479 is a single Zener diode with a nominal voltage of 39 V and a maximum power dissipation of 1.5 W. It features a maximum dynamic impedance of 30 Ohms at the test current of 6.5 mA. The device exhibits a maximum reverse leakage current of 50 nA at 31.2 V and a forward voltage of 1 V at 200 mA. It operates within a temperature range of -65°C to +175°C.

Single Zener Diodes Feature Summary

• Hermetically sealed void-less glass construction using internal metallurgical bonds for robust performance.
• Military qualified per MIL-PRF-19500/406, available in JAN, JANTX, JANTXV, and JANS reliability levels.
• Inherently radiation hard as described in Microsemi MicroNote 050.
• Non-sensitive to electrostatic discharge (ESD) per MIL-STD-750 method 1020.

Single Zener Diodes Applications

• Voltage regulation over broad operating current and temperature ranges.
• High-reliability applications where failure cannot be tolerated.
• Radiation-hardened electronic systems.

Single Zener Diodes Procurement Notes

Verify the specific ordering suffix to confirm the required reliability level (JAN, JANTX, JANTXV, or JANS) and tolerance. Ensure the package type matches the design requirements, as this series is available in both DO-41 axial-lead and D-5A MELF surface-mount configurations. Confirm RoHS compliance status if applicable, noting that compliant versions are commercial grade only.

Single Zener Diodes Selection Notes

Select based on the required Zener voltage tolerance; standard versions offer 5% tolerance, while tighter tolerances of 2% or 1% are available with specific suffixes. Consider the mounting style, choosing between the flexible axial-lead terminals of the DO-41 package or the surface-mount D-5A MELF option. Verify thermal resistance and power derating curves for the intended operating environment.

Single Zener Diodes Part Context

This component belongs to the 1N4460 through 1N4496 series of 1.5-watt glass Zener diodes. These devices are industry-recognized regulators designed for high-reliability environments. The series covers a wide voltage selection from 3.3 to 200 volts, providing versatile options for various circuit protection and regulation needs.

Single Zener Diodes Replacement Considerations

Compatible substitutes include other military-qualified 1.5 W Zener diodes meeting MIL-PRF-19500/406 specifications. Equivalent parts must match the 39 V nominal voltage, 1.5 W power rating, and hermetic sealing requirements. Surface-mount equivalents should utilize the D-5A MELF package format.