MICROSMD550LR-2

Overview

The MICROSMD550LR-2 is a surface-mount polymeric PTC resettable fuse from the microSMD series. It features a hold current of 5.5 A and a trip current of 11 A at a maximum voltage of 5 VDC. The device has a maximum resistance of 0.002 Ohms and a rated current of 50 A. It operates within a temperature range of -40°C to 80°C, with a power dissipation of 1 W. The component is housed in a 1210 (3225 Metric) package.

Feature Summary

• Provides overcurrent protection through automatic reset functionality upon fault removal
• Utilizes low-resistance polymer technology for minimal circuit impact
• Designed for surface mount assembly in compact electronic layouts

Applications

• Portable consumer electronics protection
• Battery pack circuit safeguarding
• USB peripheral interface protection

Procurement Notes

Verify component availability as this part may be obsolete or discontinued. Confirm final specifications against the manufacturer's official datasheet SCD29166 before integration. Ensure compatibility with existing PCB footprints and thermal management requirements during the sourcing process.

Selection Notes

Select this component for applications requiring high hold current in a small form factor. Evaluate the 5 VDC rating against system voltage levels. Consider the 1210 package dimensions for board space constraints. Verify thermal derating curves if operating near maximum temperature limits.

Part Context

This part belongs to Littelfuse’s microSMD family of resettable fuses. These devices offer a balance of performance and size for modern electronics. The series is designed to replace traditional fusible resistors in space-constrained designs.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.