1N4477D

Single Zener Diodes Overview

The Microchip Technology 1N4477D is a commercial-grade Zener voltage regulator diode housed in a DO-41 axial lead package. It features a nominal Zener voltage of 33 V with a tight 1% tolerance and a maximum dynamic impedance of 25 Ohms at the test current of 7.5 mA. The device supports a steady-state power dissipation of 1.5 W and operates within a junction temperature range of -65°C to +175°C. Electrical characteristics include a maximum reverse leakage current of 50 nA and a forward voltage of 1.0 V at 200 mA.

Single Zener Diodes Feature Summary

• Hermetically sealed voidless glass construction with internal metallurgical bonds for robust performance
• Triple-layer passivation provides enhanced protection against environmental factors
• Non-sensitive to electrostatic discharge per MIL-STD-750 method 1020
• Inherently radiation hard suitable for demanding operational environments

Single Zener Diodes Applications

• High-reliability voltage regulation circuits where failure cannot be tolerated
• Military and aerospace electronic systems requiring strict qualification standards
• Broad operating current and temperature range stabilization applications

Single Zener Diodes Procurement Notes

Verify that the specific ordering suffix matches the required reliability level, as the base part number denotes commercial grade. Confirm RoHS compliance status if applicable, noting that compliant versions are available only on commercial grades. Ensure the procurement documentation explicitly references the 1% tolerance designation to distinguish it from standard 5% tolerance variants within the same series.

Single Zener Diodes Selection Notes

Select this component when precise voltage regulation is critical due to its 1% tolerance specification. The 1.5 W power rating and wide thermal operating range make it suitable for high-power density designs. Verify that the system requirements align with the specified dynamic impedance and leakage current limits to ensure proper circuit functionality under varying load conditions.

Single Zener Diodes Part Context

This component belongs to the 1N4460–1N4496 series of industry-recognized Zener voltage regulators. While the base model represents commercial availability, the series is also qualified to MIL-PRF-19500/406 for JAN, JANTX, JANTXV, and JANS levels. The series offers extensive voltage selections ranging from 3.3 to 200 volts across various tolerance options.

Single Zener Diodes Replacement Considerations

Publicly confirmed parameter-equivalent substitutes include the 1N4477C (2% tolerance) and other manufacturers' equivalents such as the 1N4752A. Verify that any replacement maintains the required 1% tolerance and hermetic sealing specifications if used in high-reliability contexts.