1N4738AURE3/TR

Overview

The Microchip Technology 1N4738AURE3/TR is a single Zener diode voltage regulator designed for surface-mount applications. It features an 8.2 V nominal Zener voltage with a ±5% tolerance and a 1 W power dissipation rating. The component utilizes a DO-213AB (MELF) glass package, measuring 5.2 mm in length. Key electrical specifications include a maximum reverse leakage current of 3 µA, a Zener impedance of 7 Ohms, and a test current of 49 mA. It operates within a temperature range of -65°C to +175°C.

Feature Summary

• Surface-mount MELF glass construction for reliable automated assembly
• High thermal stability supporting extended operating temperatures up to 175°C
• Low reverse leakage current for precise voltage regulation

Applications

• Voltage reference circuits requiring stable DC levels
• Over-voltage protection stages in power supplies
• Clamping applications in signal conditioning paths

Procurement Notes

Verify the specific suffix UR3/TR against the manufacturer's latest datasheet to confirm pinout orientation and tape-and-reel specifications. Ensure the DO-213AB footprint matches your PCB design constraints. Confirm RoHS compliance status directly with the supplier documentation prior to final procurement decisions.

Selection Notes

Select this component when a robust surface-mount Zener diode is required for high-temperature environments. The DO-213AB package offers a compact alternative to axial leads while maintaining 1 W power handling. Compare the 3 µA leakage specification against circuit requirements to ensure minimal standby current impact.

Part Context

This part belongs to the standard 1N4738A series of Zener diodes, adapted for surface-mount technology. While traditional 1N4738A parts use axial DO-41 packages, the AURE3 variant adapts the same electrical characteristics into a glass MELF format. This allows designers to maintain voltage regulation performance while optimizing board space and automation compatibility.

Replacement Considerations

Direct substitutes include the onsemi 1N4738ATR and Nexperia 1N4738A,133, which share identical 8.2 V/1 W specifications but utilize different packaging formats such as axial or bulk MELF. Verify package dimensions and polarity marking alignment before substituting.