1N4739A-T

Overview

The Diodes Incorporated 1N4739A-T is a silicon planar power Zener diode housed in a DO-41 glass axial leaded package. It provides a nominal Zener voltage of 9.1 V with a standard tolerance of ±5%. The device supports a maximum power dissipation of 1.0 W at 25°C ambient temperature, derating linearly above this threshold. Electrical characteristics include a test current of 28 mA, a maximum Zener impedance of 5 Ω at the test current, and a maximum reverse leakage current of 10 µA at 7 V. The component operates within a junction and storage temperature range of -65°C to +175°C.

Feature Summary

• Utilizes a glass DO-41 case material for robust mechanical protection and thermal stability.
• Features low dynamic Zener impedance to ensure stable voltage regulation under varying load conditions.
• Compliant with RoHS directives and offers lead-free finish with solderability per MIL-STD-208.

Applications

• Voltage reference circuits requiring stable DC levels.
• Overvoltage protection stages in electronic systems.
• General-purpose voltage regulation in power supplies.

Procurement Notes

Verify that the specific ordering suffix matches the required packaging format, as the datasheet distinguishes between Ammo Pack (-A) and Tape & Reel (-T) variants. Confirm compliance requirements such as RoHS status and flammability ratings (UL 94V-0) against project specifications. Ensure the selected variant aligns with automated assembly needs if reel packaging is mandatory for the production line.

Selection Notes

Select this component when a 9.1 V regulation point is required with high power handling capabilities up to 1 Watt. Consider the thermal resistance characteristics and derating curves if the operating environment exceeds 50°C. Verify that the ±5% voltage tolerance meets the circuit precision requirements and that the axial DO-41 package fits the available board space and mounting constraints.

Part Context

This part belongs to the 1N4728A through 1N4761A series of 1.0W Zener diodes manufactured by Diodes Incorporated. The series covers a wide voltage range from 3.3V to 75V, sharing common mechanical and electrical design principles. The 1N4739A specifically targets applications needing approximately 9V regulation, fitting into the mid-range voltage segment of this established product family.

Replacement Considerations

Cross-reference with other manufacturers' 1N4739A equivalents ensuring identical DO-41 packaging, 9.1V nominal voltage, and 1W power rating. Verify that substitute parts meet the same ±5% tolerance and thermal performance limits. Note that Diodes Incorporated marks this series as not recommended for new designs, suggesting evaluation of alternative modern components.