1N4956US/TR

Overview

The Microchip Technology 1N4956US/TR is a surface mount Zener Voltage Regulator with a nominal voltage of 8.2 V and a maximum power dissipation of 5 Watts. It features a standard 5% tolerance, a test current (IZT) of 150 mA, and a dynamic impedance (ZZT) of 1.5 Ohms at the test point. The device has a maximum reverse leakage current of 600 µA at 6.2 V and a temperature coefficient of +0.06 %/°C. Maximum continuous current (IZM) is 580 mA, with a surge current capability of 24 A for an 8.3 ms square wave. It operates within a junction temperature range of -65°C to +175°C.

Feature Summary

• Military qualified to MIL-PRF-19500/356 for high-reliability applications
• Voidless hermetically sealed glass package with internal metallurgical bonds
• Triple-layer passivation and robust construction resistant to ESD
• Inherently radiation hard

Applications

• High-reliability military systems
• Critical aerospace electronics
• Harsh environment power regulation

Procurement Notes

Verify that the specific part number matches the required military qualification standards and package type. Confirm the suffix indicates tape and reel packaging if automated assembly is intended. Ensure compatibility with the specified thermal management requirements given the 5-watt power rating and operating temperature limits.

Selection Notes

Select this component when a 5-watt surface mount Zener diode with military-grade reliability is required. Consider the 8.2 V nominal voltage and 5% tolerance against circuit specifications. Evaluate the thermal resistance and derating curves for operation above 140°C ambient temperatures to ensure safe power dissipation.

Part Context

This device belongs to the 1N4954US through 1N4996US series of voidless-hermetically-sealed surface mount 5-watt glass Zener diodes manufactured by Microchip Technology's Scottsdale Division. These components are designed for applications where failure cannot be tolerated, offering extensive voltage selections from 3.3 to 390 volts in the D-5B package.

Replacement Considerations

Axial-leaded equivalents such as 1N4956 are available by deleting the US suffix. Other variants in the series include 1N4955US and 1N4957US for different voltage ratings.