SMD125F-2

Ptc Resettable Fuses Overview

The SMD125F-2 is a PolySwitch resettable fuse manufactured by Littelfuse, designed for surface-mount applications. It features a maximum voltage rating of 15 VDC and a hold current of 1.25 A. The device trips at 2.5 A and supports a maximum fault current of 40 A. Its initial resistance is 70 mOhms, rising to a maximum of 250 mOhms after tripping. Housed in a 2920 (7450 metric) package measuring 7.36 mm x 5.12 mm with a height of 3.00 mm, it operates within a temperature range of -40°C to +85°C.

Ptc Resettable Fuses Feature Summary

• Utilizes polymer PTC technology to provide automatic circuit protection that resets upon fault removal.
• Designed for surface-mount installation using standard SMD/SMT assembly processes.
• Offers high fault current tolerance up to 40 A for robust overcurrent protection.

Ptc Resettable Fuses Applications

• Overcurrent protection in portable electronic devices
• Circuit safeguarding in automotive electronics
• Protection for industrial control systems

Ptc Resettable Fuses Procurement Notes

Verify the specific datasheet version and RoHS compliance status prior to procurement, as manufacturing updates may occur. Confirm the moisture sensitivity level (MSL 2A) requirements for storage and handling during the assembly process. Ensure the selected packaging format aligns with automated placement equipment capabilities.

Ptc Resettable Fuses Selection Notes

Select this component when a 15 VDC system requires a 1.25 A hold current with a compact 2920 footprint. Consider the 2.5 A trip threshold and 40 A Imax capability against expected surge conditions. Evaluate the 70 mOhms initial resistance impact on power loss relative to alternative series options.

Ptc Resettable Fuses Part Context

This part belongs to the Littelfuse PolySwitch SMD series, which provides resettable overcurrent protection solutions. The SMD125F-2 represents a standard voltage variant within this family, distinguished by its specific 15 VDC rating and 1.25 A current characteristics compared to other series members.

Ptc Resettable Fuses Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Verify compatibility with equivalent specifications from other manufacturers if direct substitution is required.

Ptc Resettable Fuses FAQ

What is the maximum fault current rating for the SMD125F-2?

The maximum fault current (Imax) rating is 40 A.

Does the SMD125F-2 require manual replacement after a fault?

No, it is a resettable fuse that automatically returns to a low-resistance state once the overload condition is removed and the device cools down.