1N4708UR-1/TR

Overview

The Microchip Technology 1N4708UR-1/TR is a 500 mW surface mount Zener voltage regulator housed in a hermetically sealed glass DO-213AA (MELF) package. It provides a nominal Zener voltage of 22 V with a standard tolerance of ±5%. The device operates at a low test current of 50 µA and supports a junction temperature range from -65°C to +175°C. The 'TR' suffix indicates tape and reel packaging, while the '-1' suffix denotes an internally metallurgically bonded construction for enhanced reliability.

Feature Summary

• Hermetically sealed glass DO-213AA MELF surface mount package
• Internally metallurgically bonded die for high reliability
• Low Zener test current of 50 µA
• Radiation hard design

Applications

• Voltage regulation over broad operating current and temperature ranges
• High-reliability electronic circuits requiring ESD robustness
• Space or military applications utilizing MIL-PRF-19500 screening options

Procurement Notes

Verify the specific ordering suffixes to confirm exact specifications. The '-1' suffix confirms the internal metallurgical bond, which differs from standard commercial versions. The 'TR' suffix specifies tape and reel packaging; bulk quantities may vary by manufacturer lot. Confirm RoHS compliance status, as it applies only to commercial grade devices. Ensure the required voltage tolerance matches the standard ±5% unless a tighter tolerance variant is explicitly ordered.

Selection Notes

Select this component when a surface mount Zener diode with hermetic sealing and high thermal stability is required. The DO-213AA package offers a compact footprint suitable for automated assembly. Consider the 50 µA test current for low-power biasing applications. Verify that the 500 mW power dissipation rating aligns with the circuit's thermal management capabilities and ambient operating conditions.

Part Context

This part belongs to the 1N4678UR-1 through 1N4717UR-1 series of 0.5 W glass surface mount Zener diodes manufactured by Microsemi (now Microchip). The series covers a voltage selection from 1.8 V to 43 V. These devices serve as surface mount equivalents to the JEDEC registered 1N4678 through 1N4717 axial leaded series, maintaining similar electrical characteristics in a smaller form factor.

Replacement Considerations

Direct replacements include other 1N4708 variants in DO-213AA packages with matching 22 V Zener voltage and 500 mW power rating. Verify pinout polarity and hermetic sealing requirements if substituting non-MELF packages. Ensure the replacement device meets the same junction temperature and leakage current specifications.