1N4992US

Single Zener Diodes Overview

The Microchip Technology 1N4992US is a military-qualified surface mount Zener voltage regulator designed for high-reliability applications. It features a voidless hermetically sealed glass package with an internal metallurgical bond, ensuring robust construction against failure. The device operates within a temperature range of -65°C to +175°C and dissipates up to 5 Watts at a case temperature of 140°C. Key electrical parameters include a nominal Zener voltage of 270 V at a test current of 5 mA, a maximum reverse leakage current of 2 µA at 200 V, and a dynamic impedance of 800 Ohms at the test current.

Single Zener Diodes Feature Summary

• Hermetically sealed voidless-glass construction with tungsten slugs and copper end caps
• Internal Category I metallurgical bonds for enhanced structural integrity
• Triple-layer passivation providing protection against environmental stress
• Inherently radiation hard and non-sensitive to electrostatic discharge

Single Zener Diodes Applications

• High-reliability aerospace and defense circuits
• Critical power supply voltage regulation
• Harsh environment electronic systems requiring extended temperature operation

Single Zener Diodes Procurement Notes

Verify that the specific part number matches the required military qualification standard MIL-PRF-19500/356. Confirm the package type corresponds to the surface mount E (D-5B) configuration. Ensure the supplier provides documentation validating the voidless hermetic seal and metallurgical bond integrity. Check for any specific suffix requirements if tighter voltage tolerances are needed beyond the standard 5% specification.

Single Zener Diodes Selection Notes

Select this component when a high-voltage surface mount regulator is required in extreme thermal conditions. The 5 Watt power rating supports significant current handling compared to smaller packages. Verify that the PCB layout accommodates the D-5B footprint and allows for adequate heat dissipation to maintain the junction temperature within limits during continuous operation.

Single Zener Diodes Part Context

This device belongs to the 1N4954US through 1N4996US series of surface mount Zener diodes manufactured by Microsemi, now part of Microchip Technology. The series offers a wide selection of voltages from 3.3 to 390 volts in a standardized 5-watt form factor. These regulators are widely recognized in industries where component failure is not an option, serving as a reliable alternative to traditional axial-leaded equivalents.

Single Zener Diodes Replacement Considerations

For through-hole mounting requirements, the equivalent axial-leaded part numbers are 1N4992 without the US suffix. Other variants within the same series offer different voltage ratings but share identical packaging and thermal characteristics.