1N4128 (DO35)

Single Zener Diodes Overview

The Microsemi Corporation 1N4128 is a 60V Zener diode with a 5% tolerance, housed in an axial-lead glass DO-35 package. It features an internal metallurgical bond and operates within a temperature range of -65°C to +175°C. The device provides a maximum power dissipation of 0.5W at 25°C lead temperature, with linear derating to zero at 175°C. It offers low noise density and minimal capacitance, suitable for precision voltage regulation.

Single Zener Diodes Feature Summary

• Internal metallurgical bond construction
• Hermetically sealed glass DO-35 package
• Low noise density performance
• Minimal capacitance characteristics

Single Zener Diodes Applications

• Precision voltage regulation circuits
• High reliability military applications
• Radiation-hardened electronic systems

Single Zener Diodes Procurement Notes

Verify the specific suffixes required for your application. The base JEDEC number indicates standard 5% tolerance. Suffixes like '-1' denote the metallurgically bonded version. Military qualifications such as JAN, JANTX, or JANS require specific ordering codes. Commercial RoHS-compliant versions use the 'e3' suffix. Confirm lead finish options (tin-lead vs. matte-tin) based on assembly requirements.

Single Zener Diodes Selection Notes

Select this component when a hermetically sealed, low-noise Zener reference is needed in a standard axial package. Ensure the operating current stays within the specified test current limits to maintain accurate voltage regulation. Consider the thermal resistance values for proper heat dissipation design, especially if operating near the maximum power rating.

Single Zener Diodes Part Context

This part belongs to the 1N4099 through 1N4135 series of 500 mW Zener diodes. These devices are widely used in industrial and military electronics where stable voltage references are critical. The series covers a broad voltage range from 1.8V to 100V, allowing designers to select precise breakdown voltages for various circuit requirements.

Single Zener Diodes Replacement Considerations

Equivalent parts include other manufacturers' 1N4128 variants meeting MIL-PRF-19500/435 specifications. Surface mount equivalents are available in the 1N4099UR-1 series (DO-213AA package). Higher power versions exist in the 1PMT series (DO-216 package). Verify pinout compatibility and thermal characteristics when substituting.

Single Zener Diodes FAQ

What does the '-1' suffix indicate?

The '-1' suffix denotes that the device has an internal metallurgical bond, providing enhanced mechanical stability and reliability compared to non-bonded versions.

Is the 1N4128 radiation hard?

Yes, the device is inherently radiation hard, as described in Microsemi MicroNote 050, making it suitable for space and high-radiation environments.

How is the power rating affected by temperature?

The 0.5W power rating must be linearly derated starting at a lead temperature of 50°C and goes to zero at 175°C.