1N4729ATR

Overview

The Fairchild Semiconductor 1N4729ATR is a single silicon Zener diode designed for voltage regulation applications. It features a nominal Zener voltage of 3.6 V with a tolerance of ±5%. The device is rated for a power dissipation of 1 W and utilizes the DO-204AL (DO-41) through-hole glass axial package. Key electrical characteristics include a maximum reverse leakage current of 100 µA and a Zener impedance of 10 Ω at a test current of 69 mA. It operates within a temperature range of -65 °C to +200 °C.

Feature Summary

• Provides stable voltage regulation using unidirectional silicon Zener technology
• Constructed in a hermetically sealed glass axial package for durability
• Engineered for high thermal stability across a wide operating temperature range

Applications

• Voltage reference circuits requiring precise 3.6 V levels
• Overvoltage protection in low-power electronic systems
• General-purpose voltage regulation in consumer electronics

Procurement Notes

Verify the specific manufacturer source, as this part number may be distributed by entities other than Fairchild. Confirm RoHS compliance status and packaging format (reel vs. cut tape) against current distributor data sheets. Ensure the component matches the required DO-41 package dimensions and lead configuration for your PCB design before finalizing procurement.

Selection Notes

Select this component when a standard 3.6 V Zener voltage is required in a through-hole glass package. The 1 W power rating supports moderate current loads, while the ±5% tolerance ensures reasonable accuracy for general regulation tasks. Consider the DO-41 form factor for manual assembly or legacy board designs requiring axial leads.

Part Context

This component belongs to the widely recognized 1N47xx series of Zener diodes, originally standardized by JEDEC. The 'A' suffix typically denotes a tighter voltage tolerance compared to non-suffixed variants. The 'TR' suffix indicates the device is supplied in a tape and reel format suitable for automated surface mount or through-hole placement equipment.

Replacement Considerations

Compatible substitutes include the Micro Commercial Components 1N4729A-TP and the NXP/Motorola 1N4729ARL. These alternatives share identical electrical specifications and the DO-41 package, ensuring direct pin-to-pin compatibility without circuit redesign.