1N4902

Overview

The Microchip Technology 1N4902 is a silicon planar Zener diode designed for voltage regulation and reference applications. It features a nominal Zener voltage of 75 V with a 5% tolerance, rated at a test current of 3.2 mA. The device dissipates up to 500 mW of power in a DO-204AH (DO-35) axial through-hole package. Key electrical characteristics include a maximum reverse leakage current of 5 µA at the rated voltage and a Zener impedance of 130 Ohms. It operates reliably within a junction temperature range of -65°C to +175°C.

Feature Summary

• Provides stable voltage regulation using a silicon planar Zener structure.
• Engineered for high thermal stability across an extended operating temperature range.
• Offers precise voltage tolerance suitable for sensitive reference circuits.

Applications

• Voltage regulation in power supply circuits
• Precision voltage reference sources
• Overvoltage protection stages

Procurement Notes

Verify the specific manufacturer datasheet for the 1N4902 to confirm exact electrical limits and mechanical dimensions. Ensure the selected component meets the required Zener voltage tolerance and power dissipation ratings for the target application environment. Cross-reference the package style and lead configuration with the PCB layout specifications before finalizing procurement.

Selection Notes

Select this component when a 75 V regulation point is required with moderate power handling capabilities. Consider the 130 Ohm impedance value for dynamic load variations. Verify that the 500 mW dissipation rating aligns with the thermal management strategy of the host system. Confirm compatibility with the intended through-hole assembly process.

Part Context

This part belongs to the standard 1N49xx series of Zener diodes manufactured by Microchip Technology. These components are widely used in general-purpose electronics for maintaining stable DC voltages. The DO-35 axial package allows for easy integration into traditional printed circuit board designs requiring robust voltage clamping or referencing functions.

Replacement Considerations

Consult official Microchip documentation for qualified alternative part numbers within the same series. Verify that any substitute matches the 75 V nominal voltage, 500 mW power rating, and DO-35 package constraints. Ensure equivalent electrical parameters such as impedance and leakage current are met.