1N4478/TR

Single Zener Diodes Overview

The Microchip Technology 1N4478/TR is a 36 V Zener voltage regulator with a 1.5 W steady-state power dissipation rating and 27 Ohms dynamic impedance at the 7 mA test current. It features a 5% nominal voltage tolerance, 0.05 µA maximum reverse leakage current, and operates within a -65°C to +175°C junction temperature range. The component utilizes an axial-lead DO-41 package with tin/lead or matte/tin terminals over copper, weighing approximately 340 milligrams.

Single Zener Diodes Feature Summary

• Hermetically sealed void-less glass construction with internal metallurgical bonds for robust reliability.
• Triple-layer passivation providing inherent radiation hardness and non-sensitivity to electrostatic discharge.
• Flexible axial-lead mounting terminals designed for through-hole integration.

Single Zener Diodes Applications

• High-reliability military and aerospace voltage regulation
• Precision reference voltage generation in harsh environments
• Overvoltage protection circuits requiring radiation hardening

Single Zener Diodes Procurement Notes

Verify that the specific ordering suffix matches the required qualification level (JAN, JANTX, JANTXV, or JANS) and RoHS compliance status. Confirm the tape and reel packaging configuration aligns with manufacturing requirements, as standard quantities may require factory consultation. Ensure terminal plating specifications meet environmental constraints.

Single Zener Diodes Selection Notes

Select this component when a 36 V breakdown voltage and 1.5 W power handling capability are required. Evaluate the 27 Ohms dynamic impedance against circuit sensitivity needs. Consider the wide operating temperature range and hermetic sealing for applications exposed to extreme thermal cycling or vacuum conditions.

Single Zener Diodes Part Context

This device belongs to the industry-standard JEDEC registered 1N4460–1N4496 series of 1.5 Watt glass Zener diodes. Manufactured by Microchip Technology under the former Microsemi brand, it adheres to MIL-PRF-19500/406 standards for high-reliability semiconductor components used in defense and space systems.

Single Zener Diodes Replacement Considerations

Compatible equivalents include JAN1N4478US, JANTX1N4478US, JANTXV1N4478US, and JANS1N4478US. Verify that substitute part numbers maintain identical electrical characteristics and physical dimensions before implementation.

Single Zener Diodes FAQ

Is the 1N4478/TR sensitive to electrostatic discharge?

No, the device is inherently non-sensitive to ESD per MIL-STD-750 method 1020.

What is the maximum forward voltage of the 1N4478/TR?

The maximum forward voltage is 1.0 V at 200 mA and 1.5 V at 1.0 A.