1N4977

Single Zener Diodes Overview

The Microchip Technology 1N4977 is a military-qualified, voidless hermetically sealed glass Zener diode rated for 5 watts of power dissipation. It features a nominal Zener voltage of 62 V with a standard tolerance of ±5%. The device operates within a junction temperature range of -65°C to +175°C and utilizes an axial lead 'E' package. Key electrical specifications include a maximum reverse leakage current of 2 µA at 47.1 V, a dynamic impedance of 42 Ohms at the test current of 20 mA, and a forward voltage of 1.5 V at 1 A.

Single Zener Diodes Feature Summary

• Voidless hermetically sealed glass construction with internal metallurgical bonds
• Military qualification per MIL-PRF-19500/356 for high-reliability applications
• Inherently radiation hard and non-sensitive to ESD

Single Zener Diodes Applications

• High-reliability voltage regulation circuits where failure is not tolerated
• Radiation-hardened electronic systems
• Military and aerospace equipment requiring robust component construction

Single Zener Diodes Procurement Notes

Verify that the specific order matches the required military qualification level (JAN, JANTX, JANTXV, or JANS) as suffixes denote different reliability grades. Confirm compliance with RoHS directives if applicable, as standard military versions may not be compliant. Ensure the procurement documentation references the correct datasheet revision and part number to avoid substitution errors with surface-mount equivalents.

Single Zener Diodes Selection Notes

Select the 1N4977 when a 62 V reference is needed in a through-hole axial package with high thermal stability. Consider the 5 W power rating and wide operating temperature range for demanding environments. Evaluate the need for hermetic sealing and radiation hardness against cost and availability constraints compared to commercial alternatives.

Single Zener Diodes Part Context

This component belongs to the 1N4954 through 1N4996 series of 5 Watt Zener Voltage Regulators manufactured by Microsemi (now Microchip Technology). The series is designed for industry-standard applications requiring robust, hermetically sealed packages. It is distinct from the US suffix variants which offer surface-mount configurations.

Single Zener Diodes Replacement Considerations

Public confirmed substitute part numbers: JAN1N4977, JAN1N4977C, JAN1N4977CUS, JANTXV1N4977.