1N2990RB

Overview

The Microchip Technology 1N2990RB is a silicon unidirectional Zener voltage regulator diode designed for stud-mount applications. It features a nominal reference voltage of 33 V with a maximum reverse leakage current of 5 µA and a knee impedance of up to 300 Ω. The device operates within a temperature range of -65 °C to 175 °C and dissipates up to 10 W of power. Packaged in the DO-4 metal case with a round post/stud mount form factor, it connects via a single terminal where the cathode serves as the case connection.

Feature Summary

• Unidirectional voltage regulation using silicon technology
• Robust stud-mount construction for chassis integration
• Extended thermal operating capability up to 175 °C

Applications

• High-power voltage regulation circuits
• Chassis-mounted power supply protection
• Industrial equipment requiring wide temperature stability

Procurement Notes

Verify the specific manufacturer source, as this part number appears across multiple entities including Motorola/NXP, Microsemi/Microchip, and Central Semiconductor. Confirm the exact datasheet version matches your required tolerance and impedance specifications. Ensure the package type aligns with your mounting hardware requirements before finalizing procurement.

Selection Notes

Select this component when a high-power, stud-mount Zener diode is required for rigid chassis installation. The 10 W dissipation rating supports significant current handling compared to smaller packages. Verify that the 33 V breakdown voltage matches the circuit design needs and that the DO-4 package dimensions fit the available mechanical space.

Part Context

This component belongs to the standard 1N2990 series of 10-watt Zener diodes. These devices are characterized by their hermetic or robust metal packaging suitable for harsh environments. The series typically offers various voltage ratings, with the RB suffix indicating the specific 33 V variant within the product family.

Replacement Considerations

Publicly confirmed substitute part numbers are not explicitly listed in the provided documentation. Cross-referencing requires matching the 33 V, 10 W, DO-4 stud-mount specifications with equivalent offerings from other manufacturers such as Central Semiconductor or Digitron.