Resettable PTCs from Littelfuse, Inc.

Low Resistance Resettable PTCs -- nanoSMD400LR-2

Low Resistance Resettable PTCs -- nanoSMD400LR-2 -- View Larger Image
Low Resistance Resettable PTCs -- nanoSMD400LR-2-Image

The low resistivity SMD (surface-mount device) series is well suited to space-constrained mobile applications. The devices can help provide both overcurrent and overtemperature protection for battery pack PCMs (protection circuit modules) used in compact consumer devices such as smartphones and MP3/MP4 media players. In particular, the low resistivity SMD series helps battery pack suppliers achieve their design goals and simplify their installation methods.

The low resistivity SMD series comprises eleven devices. In the model number descriptions, the “micro” prefix refers to the 1210 form factor and the “nano” prefix refers to the 1206 form factor.


  • RoHS compliant
  • Halogen free (refers to: Br<=900ppm, Cl<=900ppm, Br+Cl<=1500ppm)
  • Current ratings from 1.75 to 5.0A
  • Agency recognition: UL, CSA, TÜV
  • Small footprint
  • Fast time-to-trip


  • Helps save board space and power consumption, and therefore costs, in space-constrained mobile electronics
  • Are more compact in comparison with similar offerings and are available in an industry-standard form factor
  • Can be assembled with a reflowable soldering technique, as opposed to the spot welding process required by many other components
  • Maximum electrical rating: Voltage 6VDC and short circuit current 50A
  • Industry-standard form factor of 1210 (3.0mmx2.54mm, or 0.12inx0.10in), or 1206 (3.0mmx1.52mm; or 0.12inx0.060in)
  • Useful for an operating current of 2A and above
  • Useful for and packaged for surface mounting on the PCB


  • Mobile and smart phones
  • Media players (MP3/MP4)
  • Digital still and video cameras
  • Mini notebooks
  • Tablets


Product Category
Resettable PTCs
Package Size
1206; 1206
Supply Voltage (VS)
6 volts
Trigger Current
8 amps
Current Surge
Response Time
Standards and Certifications