1N4746UR-1/TR

Overview

The Microchip Technology 1N4746UR-1/TR is a surface mountable 1.0 W glass Zener diode in the DO-213AB MELF package. It provides an 18 V nominal Zener voltage with a standard ±5% tolerance. The device operates within a temperature range of -65°C to +175°C and features a maximum dynamic impedance of 20 Ω at a test current of 14 mA. It includes a maximum reverse current of 50 µA at 13.7 V and supports a maximum regulator current of 250 mA.

Feature Summary

• Hermetically sealed glass MELF package for high reliability applications
• Surface mount design suitable for high density mounting
• Inherently radiation hard per MicroNote 050
• ESD nonsensitive construction

Applications

• Voltage regulation in high density circuits
• High reliability applications requiring source control drawings
• Low parasitic requirement environments

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm packaging configuration, as the TR suffix indicates tape and reel delivery. Confirm RoHS compliance status and screening options such as MIL-PRF-19500 prefixes if required by the application's source control drawing specifications.

Selection Notes

Select this component when a 1.0 W power dissipation rating and DO-213AB surface mount footprint are required. Ensure the 18 V breakdown voltage aligns with circuit requirements. Consider the hermetic glass construction for harsh environments where radiation hardness or strict sealing is necessary compared to plastic equivalents.

Part Context

This part belongs to the 1N4728AUR through 1N4764AUR series of surface mount Zener diodes. These devices are electrically equivalent to the JEDEC registered 1N4728A through 1N4764A axial leaded series but utilize the DO-213AB outline. The series covers Zener voltages from 3.3 V to 100 V with various tolerance options.

Replacement Considerations

The 1N4746A is the direct axial leaded equivalent. Surface mount alternatives include the SMAJ4746A series. Verify pinout compatibility and thermal derating curves when substituting packages.