1N4890

Overview

The 1N4890 is a silicon Zener diode manufactured by Microsemi Corporation. It features a nominal Zener voltage of 6.35V with a tolerance of 5%. The device is rated for a power dissipation of 0.4W and utilizes a DO-7 (DO-204AA) glass axial-leaded package. It is hermetically sealed and contains two pins.

Feature Summary

• Hermetically sealed construction using voidless glass packaging
• Internal metallurgical bond for robust mechanical integrity
• Single unidirectional Zener diode configuration

Applications

• High-reliability voltage regulation circuits
• Military and aerospace electronic systems
• Critical protection applications where failure is not tolerated

Procurement Notes

Verify the specific qualification level, as prefixes such as JAN, JANTX, or JANS denote different reliability grades within the same base part number. Confirm RoHS compliance status, as hermetic military-grade variants are typically non-compliant. Ensure the ordering suffix matches the required package style and screening standards specified in the official datasheet.

Selection Notes

Select this component when a stable 6.35V reference is required in harsh environments. The DO-7 package suits through-hole mounting. Consider tighter tolerance versions if the standard 5% variance exceeds design limits. Verify thermal management requirements against the 0.4W power rating under expected operating conditions.

Part Context

This device belongs to the industry-standard 1N4xxx series of Zener voltage regulators. It is designed for high-reliability applications requiring hermetic sealing. The product line offers various voltage selections and tolerance options to meet diverse circuit requirements in defense and space sectors.

Replacement Considerations

Cross-reference with other manufacturers offering MIL-PRF-19500 qualified equivalents. Verify pinout compatibility and physical dimensions before substitution. Ensure the replacement meets the same hermetic seal and metallurgical bond specifications.