1N4494US/TR

Single Zener Diodes Overview

The Microchip Technology 1N4494US/TR is a surface mount Zener voltage regulator with a nominal breakdown voltage of 160 V and a maximum steady-state power dissipation of 1.5 W at 25°C ambient temperature. It operates within a junction and storage temperature range of -65°C to +175°C. The device features a test current of 1.6 mA, a maximum dynamic impedance of 1000 Ohms at the test point, and a maximum reverse leakage current of 8.9 µA at 144 V. It utilizes an A (D-5A) MELF package.

Single Zener Diodes Feature Summary

• Hermetically sealed voidless glass construction using internal metallurgical bonds for robust reliability.
• Qualified per MIL-PRF-19500/406 standards for high-reliability applications where failure cannot be tolerated.
• Inherently radiation hard and non-sensitive to electrostatic discharge.

Single Zener Diodes Applications

• Voltage regulation over broad operating current and temperature ranges.
• High-reliability military and aerospace electronic systems.
• Radiation-hardened circuit protection designs.

Single Zener Diodes Procurement Notes

Verify the specific qualification level required for your application, as this series offers JAN, JANTX, JANTXV, and JANS options. Confirm that the standard 5% tolerance meets your design specifications, or check for tighter tolerance variants if necessary. Ensure compatibility with the specified surface mount MELF footprint during PCB layout.

Single Zener Diodes Selection Notes

Select this component when a hermetically sealed, radiation-tolerant Zener diode is required for extreme temperature environments up to 175°C. Consider the 1.5 W power rating and the specific 160 V breakdown voltage. Verify that the D-5A MELF package dimensions fit the available board space and soldering capabilities.

Single Zener Diodes Part Context

This part belongs to the 1N4460US through 1N4496US series of 1.5 Watt glass Zener diodes. These devices are industry-recognized for their void-less glass construction and internal metallurgical bonding. The series provides extensive voltage selections from 3.3 to 200 Volts in standard 5% tolerance packages.

Single Zener Diodes Replacement Considerations

Direct replacements must match the 160 V Zener voltage, 1.5 W power rating, and D-5A MELF package. Equivalent parts should also offer MIL-PRF-19500/406 qualification if military-grade reliability is required. Verify thermal resistance and leakage current characteristics against the original datasheet.

Single Zener Diodes FAQ

What is the maximum continuous Zener current for the 1N4494US?

The maximum continuous regulator current (IZM) is 8.9 mA.

Is the 1N4494US package lead-free?

Standard versions are not RoHS compliant. RoHS compliant versions are available only on commercial grade products.