1N5939A

Single Zener Diodes Overview

The Microchip Technology 1N5939A is a 1.5-watt glass-encapsulated Zener diode designed for voltage regulation applications. It operates within a junction temperature range of -65°C to +175°C and features a DO-41 axial leaded package. The device provides a nominal Zener voltage of 39 volts with a 10% tolerance, tested at a current of 9.6 mA. Key electrical characteristics include a maximum dynamic impedance of 45 Ohms and a reverse leakage current of 900 µA at 5.0 volts. The component supports steady-state power dissipation up to 1.5 watts at a lead temperature of 85°C.

Single Zener Diodes Feature Summary

• Hermetically sealed voidless hard glass construction with tungsten slugs for enhanced reliability and thermal performance.
• Metallurgically enhanced internal contact design providing lower thermal resistance compared to plastic-body equivalents.
• Non-sensitive to electrostatic discharge (ESD) per MIL-STD-750 method 1020 standards.
• Inherently radiation hard as described in Microsemi MicroNote 050.

Single Zener Diodes Applications

• Voltage regulation over broad operating currents and temperatures.
• High-reliability circuits requiring screening in reference to MIL-PRF-19500.
• Systems demanding hermetic sealing and high-rated temperature operation.

Single Zener Diodes Procurement Notes

Verify the specific suffix configuration against the datasheet part nomenclature to ensure correct tolerance and RoHS compliance status. Confirm that the required screening level aligns with project specifications, as military equivalent options are available separately. Check for availability of tape and reel packaging if automated assembly is required, noting that standard quantities may vary.

Single Zener Diodes Selection Notes

Select this component when a 1.5-watt power rating and hermetic glass package are necessary for harsh environments. The 10% tolerance variant suits applications where precise voltage clamping is not critical but robustness is required. Ensure the operating current remains within the specified test parameters to maintain accurate voltage regulation and impedance characteristics.

Single Zener Diodes Part Context

This device belongs to the 1N5913BG through 1N5956BG series of 1.5-watt Zener diodes manufactured by Microsemi Corporation, now part of Microchip Technology. The series covers a wide voltage range from 3.3V to 200V. The 1N5939A specifically denotes the 39V breakdown voltage within this family, utilizing the DO-41 axial leaded package format.

Single Zener Diodes Replacement Considerations

Equivalent plastic-body versions exist under the 1N5913BP – 1N5956BP designation. Surface mount alternatives include the SMBG(J)5913B–SMBG(J)5956B and SMAJ5913B–SMAJ5956B series. Verify that replacement packages meet the thermal and mechanical requirements of the original design.

Single Zener Diodes FAQ

What is the maximum power dissipation rating?

The rated average power dissipation is 1.5 W, with a steady-state limit of 1.5 W at a lead temperature of 85°C or lower.

How is polarity indicated on the device?

Polarity is marked by a band on the cathode end. For Zener regulation, the banded end must be positive with respect to the opposite end.