ST3R008B

Overview

The ST3R008B is a resettable polymeric positive temperature coefficient (PPTC) device from the Littelfuse ST Series. It functions as a self-resetting overcurrent protector with a nominal resistance of 3 ohms and a tolerance of 20%. The component is rated for a maximum operating current of 8A and features a body diameter of 24.76mm. Designed for radial lead mounting, it provides reliable circuit protection against overcurrent and short circuit conditions without requiring replacement after tripping.

Feature Summary

• Self-resetting functionality eliminates the need for manual fuse replacement after an overcurrent event
• Polymeric construction ensures stable electrical characteristics across varying environmental temperatures
• Radial leaded package design facilitates straightforward integration into standard printed circuit board layouts

Applications

• Overcurrent protection for consumer electronics power supplies
• Secondary side protection in battery-powered portable devices
• Signal line protection in telecommunications equipment

Procurement Notes

Verify that the specific part number matches the required hold current and trip characteristics for the target application. Confirm that the radial lead configuration aligns with the PCB footprint requirements. Ensure compliance with relevant safety standards applicable to the end product. Cross-reference datasheet parameters against system voltage and current limits before finalizing procurement.

Selection Notes

Select this component based on the specific 3-ohm resistance and 8A current rating requirements. Evaluate the thermal environment to ensure the device operates within its specified temperature range. Consider the physical size constraints imposed by the 24.76mm diameter. Verify compatibility with assembly processes and soldering temperatures used in the manufacturing workflow.

Part Context

This device belongs to the Littelfuse ST Series of resettable fuses, which are widely utilized for circuit protection. The series offers various current ratings and package styles to suit different electronic designs. These components serve as alternatives to traditional one-time fuses, providing cost-effective and maintenance-free protection solutions for diverse electronic applications.

Replacement Considerations

Consult official Littelfuse documentation for direct cross-references. Verify that any substitute maintains identical electrical parameters and physical dimensions.