1N6485US

Overview

The Microchip Technology 1N6485US is a surface mount Zener voltage regulator qualified to MIL-PRF-19500/406. It features a voidless hermetically sealed glass package with an internal metallurgical bond. The nominal Zener voltage is 3.3 V at a test current of 76 mA, with a maximum dynamic impedance of 10 Ohms and a maximum reverse leakage current of 50 µA at 1.0 V. Steady-state power dissipation is rated at 1.5 W at 25°C ambient temperature, with a junction-to-end cap thermal resistance of 20°C/W. Operating temperatures range from -65°C to +175°C.

Feature Summary

• Hermetically sealed voidless glass construction using internal metallurgical bonding for robust reliability.
• Military qualification per MIL-PRF-19500/406 ensuring suitability for high-reliability applications.
• Inherently radiation hard as described in Microsemi MicroNote 050.
• Non-sensitive to electrostatic discharge (ESD) per MIL-STD-750 method 1020.

Applications

• Voltage regulation over broad operating current and temperature ranges.
• High-reliability aerospace and defense circuits where failure cannot be tolerated.
• Radiation-hardened electronic systems.

Procurement Notes

Verify the specific ordering suffix against the manufacturer's datasheet to confirm the exact reliability level (JAN, JANTX, JANTXV, or JANS) and RoHS compliance status. Commercial versions may differ in termination materials and environmental specifications compared to military-grade variants. Confirm package dimensions and tape-and-reel availability directly with the factory if required.

Selection Notes

Select this component for applications requiring a 3.3 V reference with strict tolerance and low leakage characteristics. Ensure the design accommodates the 1.5 W steady-state power dissipation limit and the specified thermal resistance. Verify that the operating environment falls within the -65°C to +175°C junction temperature range and meets the radiation hardness requirements outlined in the documentation.

Part Context

This device belongs to the 1N6485US–1N6491US series of surface mount Zener diodes. These regulators are designed as surface mount equivalents to popular JEDEC registered axial-lead series. The series offers Zener selections from 3.3 to 200 volts with standard 5% tolerance, alongside tighter 1% and 2% tolerance options available via specific ordering suffixes.

Replacement Considerations

Consult the official datasheet for direct cross-reference information. No public substitute part numbers are confirmed in the provided source material.