SL221R520B

Inrush Current Limiters (ICL) Overview

The Vishay Ametherm SL221R520B is a Negative Temperature Coefficient (NTC) thermistor inrush current limiter from the SL22 series. It features a nominal resistance of 1.5 Ohms and a steady-state current rating of 20 A. The component has a diameter of 22 mm and utilizes radial leads with a 7.8 mm spacing for PCB mounting. It is designed to withstand high input energy levels, supporting up to 36 amperes of continuous current and 260 joules of input energy. The device operates within voltage ratings of 115 VAC and 230 VAC.

Inrush Current Limiters (ICL) Feature Summary

• High thermal stability capable of withstanding significant input energy pulses
• Designed for robust protection against high inrush currents in AC circuits
• Radial leaded construction suitable for standard PCB mounting techniques

Inrush Current Limiters (ICL) Applications

• Protection for AC motors and motor drives
• Power supply input stage surge suppression
• Audio amplifier circuit protection
• Battery charger inrush limiting

Inrush Current Limiters (ICL) Procurement Notes

Verify the specific suffix 'B' against official Vishay documentation to confirm if it denotes a specific tolerance, packaging variation, or regional compliance requirement distinct from the base SL221R520 model. Ensure the procurement channel provides traceable datasheets matching this exact part number to avoid substitution errors with similar SL22 variants.

Inrush Current Limiters (ICL) Selection Notes

Select this component when the application requires a 1.5 Ohm initial resistance to limit startup surges while handling a 20 A steady-state load. The 22 mm form factor and 260 Joule energy rating make it suitable for medium-power AC applications where higher thermal mass is needed compared to smaller ICLs. Verify that the 7.8 mm lead pitch fits the target PCB layout.

Inrush Current Limiters (ICL) Part Context

This part belongs to the SL22 series of inrush current limiters manufactured by Vishay Ametherm. The series is characterized by its use in protecting electronic equipment from damaging current spikes during power-up. The SL22 family offers various resistance and current combinations tailored for different power levels, all sharing a common 22 mm disc geometry.

Inrush Current Limiters (ICL) Replacement Considerations

Public confirmed substitute part numbers are not available in the provided source data. Cross-referencing with other Vishay SL22 models requires careful verification of electrical parameters such as resistance, current rating, and energy absorption capabilities to ensure functional compatibility.