1N4556RB

Single Zener Diodes Overview

The Microchip Technology 1N4556RB is a high-power 50 W Zener diode with a nominal voltage of 7.5 V and a tolerance of ±5%. It utilizes a DO-5 (DO-203AB) hermetically sealed metal-glass package featuring an 11/16 inch hexagonal stud. The 'R' suffix indicates reverse polarity, connecting the cathode to the case. Electrical characteristics include a maximum dynamic impedance of 0.24 Ω at a test current of 1,650 mA and a maximum reverse current of 10 µA at 3.0 V.

Single Zener Diodes Feature Summary

• Hermetically sealed welded construction for environmental protection
• Internal solder bond construction for mechanical stability
• Reverse polarity configuration with cathode connected to the case
• Inherently radiation hard design

Single Zener Diodes Applications

• Voltage regulation in aerospace and defense systems
• High power dissipation circuits requiring stud mounting
• Military qualification applications per MIL-PRF-19500/358

Single Zener Diodes Procurement Notes

Verify that the specific order includes the 'R' suffix to confirm reverse polarity (cathode-to-case), as standard units feature anode-to-case connections. Confirm the 'B' suffix is present to ensure the required ±5% voltage tolerance. Ensure the procurement specification explicitly requires the hermetically sealed DO-5 package suitable for stud mounting.

Single Zener Diodes Selection Notes

Select this component when a 7.5 V reference with tight ±5% tolerance is required in a high-power environment. The reverse polarity design is critical for applications where the chassis must serve as the cathode connection. Verify that the thermal management system can maintain the case temperature below 75°C to support the full 50 W rating without derating.

Single Zener Diodes Part Context

This device belongs to the 1N4549B through 1N4556B series of 50 Watt Zener diodes manufactured by Microsemi's Scottsdale Division. These components are JEDEC registered and designed for robust operation across a wide temperature range from -65°C to +175°C. The series offers broad voltage coverage from 3.9 V to 200 V in a standardized industrial package.

Single Zener Diodes Replacement Considerations

Equivalent parts within the same series include 1N4556B (standard polarity). For identical electrical performance but different polarity, use 1N4556A. Military qualified versions such as JANTX1N4556RB or JANTXV1N4556RB provide enhanced screening levels.