1N4897A

Overview

The Microchip Technology 1N4897A is a temperature-compensated Zener diode designed for precision voltage reference applications. It features a nominal Zener voltage of 99V with a maximum power dissipation of 0.5W at 25°C ambient temperature. The device operates within a junction temperature range of -55°C to +100°C and utilizes an axial DO-35 (DO-204AA) glass passivated package. Key electrical characteristics include a reverse current of 5µA maximum and a Zener impedance of 400Ω, ensuring stable performance in demanding electronic circuits.

Feature Summary

• Temperature compensated design for enhanced voltage stability across operating ranges
• Glass passivated construction for environmental protection and reliability
• Axial leaded package suitable for through-hole mounting

Applications

• Precision voltage reference circuits
• Voltage regulation systems requiring high stability
• Overvoltage protection networks

Procurement Notes

Verify the specific manufacturer source, as multiple entities including Digitron Semiconductors produce this part number. Confirm RoHS compliance status directly with the supplier, as historical data indicates variations. Ensure the package type matches the required DO-35 form factor. Cross-reference datasheets from authorized distributors to validate electrical parameters against the official Microchip specification sheet before integration into critical designs.

Selection Notes

Select this component when a stable 99V reference is required with minimal temperature drift. Compare Zener impedance and reverse leakage specifications against circuit requirements. Consider the 0.5W power rating and thermal management needs for the intended operating environment. Verify that the axial package fits the PCB layout constraints compared to surface-mount alternatives.

Part Context

This component belongs to the standard Zener diode family used in analog signal processing and power management. It serves as a fundamental passive element for establishing fixed potential points in electronic schematics. The 1N4897A variant specifically addresses applications where voltage accuracy must remain consistent despite thermal fluctuations, distinguishing it from standard Zener diodes lacking compensation features.

Replacement Considerations

Direct substitutes may include other manufacturers' versions of the 1N4897A, such as those from Digitron Semiconductors. Verify pinout compatibility and ensure equivalent electrical ratings for voltage, power, and impedance. Check for any differences in package dimensions or lead spacing if mechanical fit is critical.