1N4746A

Overview

The Microchip Technology 1N4746A is a single silicon Zener diode designed for voltage regulation applications. It features a nominal Zener voltage of 18 V with a tolerance of ±5%. The device supports a maximum power dissipation of 1 W and operates within an extended temperature range from -65°C to +200°C. Key electrical characteristics include a maximum reverse leakage current of 5 µA at 13.7 V, a Zener impedance of 20 Ohms, and a test current of 14 mA. It is housed in a DO-204AL (DO-41) axial through-hole package.

Feature Summary

• Provides stable voltage regulation with a nominal 18 V output.
• Capable of handling up to 1 W of power dissipation.
• Engineered for high-temperature operation up to 200°C.
• Constructed using silicon material for reliable performance.

Applications

• General-purpose voltage reference circuits
• Overvoltage protection stages
• Power supply regulation modules

Procurement Notes

Verify the specific manufacturer designation, as the 1N4746A part number is utilized by multiple semiconductor producers including Central Semiconductor and Vishay. Confirm that the required RoHS compliance status aligns with project specifications, noting that some Microchip variants may not meet current environmental standards. Ensure the selected supplier provides the correct DO-41 package configuration and valid datasheet documentation before finalizing procurement orders.

Selection Notes

Select this component when a robust 18 V regulation point is required in through-hole designs. The wide operating temperature range makes it suitable for harsh environments where standard commercial parts would fail. Verify that the circuit can accommodate the specified 20 Ohm dynamic impedance and 5 µA leakage current to ensure proper signal integrity and noise performance in sensitive analog sections.

Part Context

This device belongs to the widely recognized 1N47xx series of Zener diodes, which are standard components for basic voltage clamping and regulation tasks. The 1N4746A specifically denotes the 18 V variant within this family. While originally standardized under older JEDEC numbering systems, modern production continues under various manufacturers, maintaining consistent electrical parameters across different supply chains.

Replacement Considerations

• 1N4746A (onsemi)
• 1N4746A (Nexperia USA Inc.)