1N4729A

Overview

The SMC Diode Solutions 1N4729A is a 1.0 W silicon Zener diode with a nominal voltage of 3.6 V and ±5% tolerance. It operates in the -65 °C to +200 °C range using a DO-41 glass axial package. Key electrical parameters include a maximum reverse leakage current of 100 µA, a Zener impedance of 10 Ω at 69 mA test current, and a forward voltage of 1.2 V at 1 A. The device features a metallurgically bonded junction for reliability.

Feature Summary

• Hermetically sealed glass construction for environmental protection
• Planar die design ensuring stable voltage regulation
• High thermal stability supporting extended temperature ranges

Applications

• Voltage reference circuits
• Overvoltage protection stages
• Biasing networks in analog systems

Procurement Notes

Verify the specific manufacturer designation as SMC Diode Solutions may utilize different suffixes or legacy part numbers compared to standard JEDEC identifiers. Confirm RoHS compliance status and exact datasheet revision before ordering, as availability varies by distributor. Ensure the DO-41 package dimensions match your PCB footprint requirements.

Selection Notes

Select this component when a precise 3.6 V reference is required with low dynamic impedance. The DO-41 package suits through-hole assembly processes. Consider the 100 µA leakage limit for high-impedance input applications. Verify that the 1 W power dissipation rating accommodates the expected thermal environment without excessive derating.

Part Context

This part belongs to the standard 1N47xx series of 1 Watt Zener diodes. These components are widely used in general-purpose electronics for voltage stabilization. The 1N4729A specifically targets the 3.6 V segment of this family, offering a balance between low voltage regulation and moderate power handling capabilities for discrete circuit designs.

Replacement Considerations

Direct substitutes include the NXP 1N4729ARL and Vishay 1N4729A-TR. These alternatives share identical electrical specifications and DO-41 packaging. Verify pinout compatibility and thermal characteristics before substituting in existing designs.