1N4742UR-1/TR

Overview

The Microchip Technology 1N4742UR-1/TR is a surface mountable 1.0 W glass Zener diode in the DO-213AB MELF package. It provides a nominal Zener voltage of 12 V with a standard tolerance of +/- 5%. Electrical characteristics include a test current (IZT) of 21 mA, maximum dynamic impedance (ZZT) of 9 Ohms at IZT, and maximum reverse current (IR) of 1 µA at VR = 1 V. The device supports a maximum regulator current (IZM) of 76 mA and features an operating temperature range from -65°C to +175°C.

Feature Summary

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

Applications

• Voltage regulation over broad operating current and temperature ranges
• High density electronic circuit assembly
• Applications requiring hermetic sealing and source control drawing compliance

Procurement Notes

Verify that the ordering suffix 'TR' confirms tape and reel packaging as specified in the datasheet. Confirm the absence of the 'A' suffix indicates the standard 10% voltage tolerance rather than the 5% tolerance associated with the 'A' designation. Ensure the component meets the specific JEDEC outline DO-213AB dimensions required for the target footprint.

Selection Notes

Select this component when a 12 V Zener reference is needed in a surface mount form factor. The DO-213AB package offers a leadless profile compared to axial equivalents. Consider the thermal resistance of 130°C/W junction to ambient on FR4 when designing heat dissipation. Verify that the 1.0 W power rating aligns with the steady-state power requirements of the application.

Part Context

This part belongs to the 1N4728UR thru 1N4764AUR series, which are electrically equivalent to the registered 1N4728A thru 1N4764A series but packaged in the JEDEC surface mount outline DO-213AB. The series covers Zener voltages from 3.3 V to 100 V. This specific model corresponds to the 12 V variant within the broader family of surface mount glass Zener diodes.

Replacement Considerations

The 1N4742A is the electrical equivalent in the DO-41 axial package. Surface mount equivalents such as SMAJ4742A are also available. For tighter tolerances, variants with C (+/- 2%) or D (+/- 1%) suffixes exist within the same series.