1N5518C

Overview

The Microchip Technology 1N5518C is a silicon unidirectional Zener diode with a nominal voltage of 3.3V and a power dissipation rating of 0.5W. It utilizes the DO-204AH (DO-35) glass axial-leaded package, featuring two pins. The device operates within a temperature range of -65°C to 175°C and exhibits a maximum dynamic impedance of 26 Ω. This component serves as a low-voltage avalanche diode suitable for precise voltage regulation tasks.

Feature Summary

• Provides stable voltage regulation across a broad operating current and temperature range
• Features internal metallurgical bond construction for enhanced reliability in harsh environments
• Offers hermetic sealing within a glass DO-35 package for environmental protection

Applications

• Voltage regulation in power supply circuits
• Overvoltage protection for sensitive electronic components
• Reference voltage generation in precision measurement systems

Procurement Notes

Verify that the specific part number suffix matches the required tolerance and qualification level, as variations exist between commercial and military grades. Confirm package integrity and lead finish specifications against project requirements. Ensure sourcing from authorized distributors to guarantee authenticity and traceability for critical applications.

Selection Notes

Select this component when a 3.3V reference is needed with high thermal stability up to 175°C. The DO-35 package suits through-hole designs requiring robust mechanical mounting. Consider the 26 Ω dynamic impedance for circuit noise sensitivity. Verify if tighter voltage tolerances or surface mount alternatives are necessary for the specific design constraints.

Part Context

This device belongs to the 1N5518 series of low-voltage avalanche Zener diodes manufactured by Microchip Technology. The series covers voltages from 3.3V to 33V with various tolerance options. The 1N5518C specifically denotes the 3.3V variant in the standard commercial or qualified line, distinct from the surface mount BUR-1 variants.

Replacement Considerations

Equivalent JEDEC registered parts include the 1N5518B series. Surface mount equivalents are available in the MLL5518B-1 series. Cross-reference datasheets for exact impedance and leakage current matching before substitution.