TDK – EPCOS PTC Thermistors : Superior Solutions for Circuit Protection

PTC Inrush Current Limiters

NTC thermistors are not always the solution of choice as inrush current limiters (ICLs) in power supplies. In certain cases with especially demanding temperature and power conditions, PTC (Positive Temperature Coefficient) thermistors are able to offer more reliable protection. EPCOS PTC ICLs (Inrush Current Limiters) offer key benefits when used as ICL components for active inrush current limitation in certain applications.

• Their ICL functionality is not affected by extreme operating temperatures.
• Effective in-rush current limiting as soon as load is turned off; cooling already takes place during normal operation.
• They are self-protecting against current overloads caused by circuit malfunctions.

Thanks to the broad portfolio of EPCOS PTC ICLs, power supplies can be reliably protected from high inrush currents and short circuits under demanding temperature conditions.

PTC Superior Series
EPCOS SMD PTC Superior Series is the ideal component for over temperature sensing and is used to monitor potential overheating conditions and can be used as a current regulator, thereby offering a thermal shutdown as the applied current load decreases at high temperature.

Possible applications for these temperature limit sensors are power supplies such as AC/DC and DC/DC converters, battery chargers and packs or lamp ballasts. The SMD PTC thermistors can be used in the fan controllers of notebooks in order to avoid critical temperatures. In automotive electronics, they are suitable for applications such as the temperature monitoring of LED-based lighting systems.


  • Qualification based on AEC-Q200 rev. D
  • Fast and reliable response
  • UL1434 and ULc approvals
  • Suitable for reflow soldering process
  • Operating temperature range -40°C to +150°C
  • Case sizes 0402, 0603, and 0805


  • Power supplies (Switch Mode Power Supplies)
  • LED lighting
  • On-board DC/DC converters
  • Telecom – data processing DC/DC converters
  • Battery chargers and packs