1N4551RB

Single Zener Diodes Overview

The Microchip Technology 1N4551RB is a high-power 50 W Zener diode from the 1N4549B through 1N4556B series. It provides voltage regulation with a nominal Zener voltage of 5.1 V at a test current of 2,450 mA and a maximum dynamic impedance of 0.12 Ω. The device features reverse polarity (cathode to case) indicated by the 'R' suffix and offers a standard tolerance of ±5%. It operates within a junction temperature range of -65°C to +175°C and utilizes a DO-5 (DO-203AB) hexagonal stud package.

Single Zener Diodes Feature Summary

• Hermetically sealed welded metal and glass construction for durability
• Internal solder bond design ensuring robust mechanical integrity
• Reverse polarity configuration with cathode connected to the case
• Inherently radiation hard characteristics suitable for harsh environments

Single Zener Diodes Applications

• Voltage regulation in aerospace and defense systems
• Power supply protection circuits requiring high power dissipation
• Industrial applications demanding wide operating temperature ranges

Single Zener Diodes Procurement Notes

Verify that the specific part number includes the 'R' suffix to confirm reverse polarity orientation, as standard units feature anode-to-case connections. Ensure the procurement specification explicitly requires the 5% tolerance ('B' suffix) to match the electrical characteristics defined in the datasheet. Confirm the package type matches the DO-5 hexagonal stud requirement for proper mounting hardware compatibility.

Single Zener Diodes Selection Notes

Select this component when designing circuits requiring 50 W power dissipation capabilities and precise voltage regulation near 5.1 V. Consider the thermal resistance of 2.0 °C/W maximum and the necessity for adequate heat sinking above 75°C case temperature. Evaluate the reverse polarity requirement against board layout constraints, as the cathode must be electrically connected to the mounting base.

Single Zener Diodes Part Context

This component belongs to the Microsemi Scottsdale Division 1N4549B through 1N4556B series of high-power Zener diodes. These devices are JEDEC registered and offer a broad voltage selection from 3.9 V to 200 V. The series is designed for critical applications where reliability under extreme thermal and environmental conditions is essential.

Single Zener Diodes Replacement Considerations

Equivalent parts include the 1N4551B for standard polarity or other 1N4549B-1N4556B variants for different voltage levels. Military qualified versions such as JANTX1N4551B or JANTXV1N4551B provide enhanced screening but maintain identical electrical specifications.