2N5247

Overview

The Fairchild Semiconductor 2N5247 is a silicon unidirectional Zener diode housed in the DO-35 axial leaded package. It features a nominal Zener voltage of 17 V with a standard tolerance of ±5%. The device is rated for a maximum power dissipation of 0.5 W at an ambient temperature of 75°C, with a peak junction temperature capability of 175°C. Key electrical characteristics include a maximum dynamic impedance of 19 Ω and a specified reverse current level. The component utilizes a glass case construction and is designed for general-purpose voltage regulation and reference applications within discrete semiconductor circuits.

Feature Summary

• Utilizes a DO-35 glass axial leaded package for through-hole mounting
• Provides stable 17 V reference voltage with ±5% tolerance
• Supports continuous power dissipation up to 0.5 W
• Constructed from silicon material for reliable unidirectional operation

Applications

• General-purpose voltage regulation in low-power circuits
• Voltage reference sources for analog signal conditioning
• Overvoltage protection for sensitive input stages

Procurement Notes

Verify compliance status prior to procurement, as specific manufacturing lots may carry non-RoHS certification depending on production date and region. Confirm the exact suffix or revision code matches project requirements, as packaging variations exist. Ensure thermal management strategies account for the 0.5 W dissipation limit at elevated ambient temperatures to maintain junction temperature within safe operating limits during continuous operation.

Selection Notes

Select this component when a standard 17 V Zener reference is required in a DO-35 form factor. Evaluate the 19 Ω dynamic impedance against circuit sensitivity requirements, as lower impedance variants exist for tighter regulation needs. Consider the ±5% tolerance band for budgeting voltage accuracy in precision designs. Verify that the axial lead configuration aligns with available PCB footprint constraints compared to surface-mount alternatives like MMBZ5247.

Part Context

The 2N5247 belongs to the widely recognized 1N52xx series of Zener diodes, originally standardized for military and industrial specifications. Fairchild Semiconductor produced this component as part of its extensive discrete diode portfolio before operational transitions. The DO-35 package remains a legacy standard for through-hole designs, ensuring compatibility with older equipment architectures while maintaining availability for replacement and maintenance scenarios.

Replacement Considerations

Equivalent parts include the 1N5247B and 1N5247BT50R, which share identical electrical parameters and pinout configurations. Cross-reference with Vishay or ON Semiconductor equivalents such as BZX55C17 for functional substitution. Verify package compatibility and tolerance markings when replacing units from different manufacturers to ensure mechanical fit and electrical performance alignment.