1N2819A

Overview

The Microchip Technology 1N2819A is a silicon unidirectional Zener voltage regulator diode designed for high-power applications. It features a nominal Zener voltage of 22 V with a maximum power dissipation of 50 W. The device utilizes a TO-204AD (TO-3) through-hole package, where the case is electrically connected to the cathode. Key electrical specifications include a knee impedance of up to 80 Ω and a maximum reverse current of 5 µA. It operates within a temperature range of -65 °C to 175 °C.

Feature Summary

• High power handling capability with 50 W maximum dissipation
• Robust metal flange mount construction for effective thermal management
• Unidirectional voltage regulation with stable 22 V reference
• Direct case-to-cathode electrical connection for mounting flexibility

Applications

• High-power voltage regulation circuits
• Industrial power supply protection
• Overvoltage clamping in heavy-duty equipment

Procurement Notes

Verify the manufacturer source carefully, as this component has been produced by multiple entities including Motorola, Microsemi, and Microchip. Confirm the specific datasheet version and tolerance class (e.g., 'A' suffix) required for your design. Ensure the TO-204AD package dimensions match your mechanical constraints. Check for RoHS compliance status if environmental regulations apply to your project.

Selection Notes

Select this component when a robust, high-current Zener diode is needed for voltage stabilization. The TO-3 package requires appropriate heatsinking due to the 50 W rating. Consider the 22 V nominal voltage and 5 µA leakage current against circuit requirements. Verify that the unidirectional configuration suits the polarity needs of the application compared to bidirectional alternatives.

Part Context

The 1N2819A belongs to the legacy series of high-power silicon Zener diodes originally standardized for military and industrial use. It represents a transition from smaller signal diodes to components capable of handling significant energy loads. The part number structure indicates a specific voltage and power class within the broader family of regulated diodes used in critical infrastructure.

Replacement Considerations

Equivalent parts include JAN1N2819RB from NXP/Motorola. Verify pinout compatibility and thermal resistance values before substitution. Ensure the replacement maintains the 50 W power rating and 22 V Zener voltage specification.