1N3305RB

Overview

The Microchip Technology 1N3305RB is a high-power 50 W Zener diode from the JEDEC registered 1N3305 series. It provides voltage regulation with a nominal Zener voltage of 6.8 V at a test current of 1,850 mA. The device features a maximum dynamic impedance of 0.20 Ohms and a reverse current of 300 µA. It utilizes a DO-5 (DO-203AB) package with a hexagonal stud for mounting. The component operates within a junction temperature range of -65°C to +175°C and includes an 'R' suffix indicating reversed polarity where the cathode connects to the case.

Feature Summary

• Hermetically sealed welded construction with internal solder bond
• Reversed polarity configuration with cathode connected to the case
• Radiation hard design inherent to the component structure
• ESD nonsensitive per MIL-STD-750 Method 1020

Applications

• Voltage regulation in power supplies requiring broad operating current ranges
• High power dissipation applications utilizing adequate heat sinking
• Military and aerospace systems requiring radiation hardness

Procurement Notes

Verify that the specific part number includes the 'R' suffix to confirm reversed polarity orientation, as standard units feature anode-to-case connections. Confirm military qualification requirements such as JAN or JANTX prefixes if applicable to the system specifications. Ensure thermal management designs account for the 50 W power rating and the specified derating curve above 75°C case temperature.

Selection Notes

Select this component when a 6.8 V regulation point is required with high power handling capabilities. The reversed polarity option is suitable for designs where the case must serve as the cathode terminal. Consider the DO-5 package dimensions and hexagonal stud threading for mechanical integration. Evaluate thermal resistance characteristics to ensure effective heat dissipation under maximum load conditions.

Part Context

This device belongs to the 1N3305 through 1N3350B series of 50 Watt Zener diodes manufactured by Microsemi Scottsdale Division. The series covers a voltage range from 3.9 V to 200 V. These components are designed for robust performance in demanding environments and are available in various military screening levels including JAN, JANTX, and JANTXV qualifications.

Replacement Considerations

Consult factory documentation for surface mount equivalents. Verify compatibility with existing thermal interfaces and mounting hardware due to the specific DO-5 hexagonal stud requirement.