Inrush current limiting PTC thermistors for automotive and industrial applications

Vishay Intertechnology, Inc. has released a new series of inrush current-limiting PTC thermistors. Designed to increase performance in active charge and discharge circuits for automotive and industrial applications, the Vishay BCcomponents PTCEL series devices combine a broad range of resistance at 25C (R25) values with high voltage and energy handling capabilities.

Featuring R25 values from 60-Ohm to 1kOhm, the devices released today enable high maximum voltages of 1000VDC at 500-Ohm and 1200VDC at 1kOhm, and maximum energy handling to 240J – four times higher than competing devices. Combining multiple thermistors in parallel can achieve energy absorption levels over 1000J. With their high temperature operation to +105C, the PTCEL series provides a heat capacity to 2.3J/K for all resistance values.

AEC-Q200 qualified and self-protecting – with no risk of over-heating – the thermistors provide overload protection in AC/DC and DC-DC converters; load dump, DC-Link, battery management, and emergency discharge circuits; onboard chargers; home energy storage systems; motor drives; and welding equipment. The devices withstand >100,000 inrush-power cycles for these applications and are highly resilient against non-switching peak power up to 25kW.

The series is available in two sizes: the smaller PTCEL13R and larger PTCEL17 for low and high-energy applications, respectively. All devices are available in tape-on-reel packaging and offer a leadwire pitch of 5mm. In addition, the PTCEL17R is available with leadwire pitches of 7.5mm and 10mm to accommodate their higher voltages. It can also be automatically handled by pick-and-place equipment for lower placement costs.

The barium titanate thermistors consist of a ceramic pellet soldered between two tinned CCS wires and coated with a UL 94 V-0 compliant high-temperature silicone lacquer. The RoHS-compliant devices are C-UL-US recognized under file E148885 for AC and DC use, providing an increased and controlled safety level. SPICE and 3D models for the PTCEL13R and PTCEL17R are available.