1N4476D

Single Zener Diodes Overview

The Microchip Technology 1N4476D is a military-qualified Zener voltage regulator diode designed for high-reliability applications. It features a hermetically sealed void-less glass package with an internal metallurgical bond. The device provides a nominal Zener voltage of 30 V with a tight tolerance of ±1%, indicated by the 'D' suffix. It operates within a junction temperature range of -65°C to +175°C and dissipates up to 1.5 W at a lead temperature of +112°C. Key electrical parameters include a test current of 8.5 mA, a maximum dynamic impedance of 20 Ohms, and a maximum reverse leakage current of 50 µA.

Single Zener Diodes Feature Summary

• Hermetically sealed void-less glass construction with internal metallurgical bonding for robustness.
• Military qualification per MIL-PRF-19500/406 standards.
• Triple-layer passivation for enhanced protection.
• Inherently radiation hard.

Single Zener Diodes Applications

• High-reliability aerospace systems
• Defense electronics
• Critical voltage regulation circuits

Single Zener Diodes Procurement Notes

Verify that the ordering suffix matches the required reliability level (JAN, JANTX, JANTXV, or JANS) and tolerance ('D' for 1%). Confirm RoHS compliance status, as commercial versions may differ from military specifications. Ensure the package type aligns with the design requirements, typically DO-41 axial lead. Check for specific lot traceability requirements mandated by the application.

Single Zener Diodes Selection Notes

Select this component when a precise 30 V reference with ±1% tolerance is required in harsh environments. The 1.5 W power rating supports steady-state operation at elevated temperatures. Consider the thermal resistance of 42°C/W for heat dissipation calculations. The wide operating temperature range ensures functionality across extreme conditions without derating below specified limits.

Single Zener Diodes Part Context

This part belongs to the 1N4460–1N4496 series of 1.5 Watt Glass Zener Diodes. The series offers various voltage selections from 3.3 V to 200 V. Standard tolerances are ±5%, while tighter options like ±2% and ±1% are available via specific suffixes. The series is widely recognized for its durability and consistent performance in demanding electronic designs.

Single Zener Diodes Replacement Considerations

Direct substitutes must match the 30 V Zener voltage, 1.5 W power rating, and ±1% tolerance. Verify that any replacement also meets MIL-PRF-19500/406 qualifications if military-grade reliability is required. Package compatibility (DO-41) and pinout orientation must be confirmed before substitution.

Single Zener Diodes FAQ

What does the 'D' suffix indicate in the 1N4476D part number?

The 'D' suffix denotes a voltage tolerance of ±1%, which is tighter than the standard ±5% tolerance found in non-suffixed parts.

Is the 1N4476D radiation hard?

Yes, the datasheet states that the device is inherently radiation hard as described in Microsemi MicroNote 050.

What is the maximum continuous Zener current for the 1N4476D?

The maximum continuous regulator current (IZM) is 48 mA.