1N4749A-T

Overview

The 1N4749A-T is a single Zener diode manufactured by Vishay General Semiconductor - Diodes Division. It features a nominal Zener voltage of 24 V with a tolerance of ±5%. The device has a maximum power dissipation of 1.3 W and operates in the DO-204AL (DO-41) axial through-hole package. Key electrical parameters include a maximum dynamic impedance (Zzt) of 25 Ohms, a forward voltage of 1.2 V at 200 mA, and a reverse leakage current of 5 µA at 18.2 V. It is rated for an operating junction temperature up to 175°C and holds AEC-Q101 automotive qualification.

Feature Summary

• Provides stable voltage regulation with a nominal 24 V reference point.
• Constructed in a hermetically sealed glass passivated DO-204AL axial package.
• Qualified for automotive applications under the AEC-Q101 standard.

Applications

• Low voltage stabilizers
• Voltage reference circuits
• Overvoltage protection

Procurement Notes

Verify the specific suffix against official datasheets, as variations like -TR or -TAP may indicate different packaging formats such as tape and reel or ammo pack. Confirm that the requested part matches the 1.3 W power rating and AEC-Q101 qualification if automotive grade is required. Ensure the manufacturer is explicitly listed as Vishay General Semiconductor - Diodes Division to avoid confusion with other vendors producing similar part numbers.

Selection Notes

Select this component when a robust, axial-leaded Zener diode is needed for high-power dissipation relative to its size. The 1.3 W rating allows for higher current handling compared to standard 1 W variants. Consider the 25 Ohm dynamic impedance for applications requiring moderate regulation accuracy. The DO-204AL package is suitable for through-hole mounting on PCBs where space is not severely constrained.

Part Context

This component belongs to the 1N47xx series of low-voltage regulator diodes produced by Vishay. The series offers various voltage options from 3.3 V to 24 V in the same DO-41 glass package. The 1N4749A variant specifically targets the 24 V segment, providing a reliable solution for general-purpose voltage regulation tasks in industrial and consumer electronics.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Other manufacturers produce equivalent 24 V 1W/1.3W Zener diodes in DO-41 packages, but direct cross-referencing requires consulting individual manufacturer substitution guides.