1N4978

Single Zener Diodes Overview

The Microchip Technology 1N4978 is a military-qualified, voidless hermetically sealed glass Zener diode designed for high-reliability applications. It features a 5-watt power dissipation rating and operates within a temperature range of -65°C to +175°C. The device provides a nominal Zener voltage of 68V with a standard tolerance of ±5%. Electrical characteristics include a maximum reverse leakage current of 2µA at 51.7V and a maximum Zener impedance of 50 Ohms at the test current of 20mA. It utilizes an axial lead 'E' package.

Single Zener Diodes Feature Summary

• Hermetically sealed voidless-glass construction with internal metallurgical bonds
• Military qualification per MIL-PRF-19500/356
• Inherently radiation hard
• ESD nonsensitive per MIL-STD-750 Method 1020

Single Zener Diodes Applications

• High-reliability aerospace systems
• Defense electronics requiring failure-intolerant components
• Industrial equipment operating in extreme temperatures
• Voltage regulation circuits in harsh environments

Single Zener Diodes Procurement Notes

Verify that the specific part number matches the required military specification level (JAN, JANTX, or JANS) as suffixes define the quality tier. Confirm the package type corresponds to the axial lead configuration. Ensure compliance with the manufacturer's environmental declarations and material composition requirements before finalizing procurement orders.

Single Zener Diodes Selection Notes

Select this component when a robust 5W Zener regulator is needed for critical infrastructure. The wide operating temperature range supports demanding thermal conditions. Verify that the 68V breakdown voltage aligns with circuit design requirements. Consider the physical dimensions of the axial lead package for PCB layout constraints.

Single Zener Diodes Part Context

This component belongs to the 1N4954 through 1N4996 series of 5-watt Zener diodes manufactured by Microsemi (now Microchip Technology). These devices are industry-standard regulators known for their durability and consistent performance in regulated power supply applications across various sectors.

Single Zener Diodes Replacement Considerations

Equivalent parts from other manufacturers must match the 68V Zener voltage, 5W power rating, and axial lead package. Verify that substitute components meet the same MIL-PRF-19500/356 military qualification standards if reliability is critical.