New Ametherm Thermistors Deliver Industry-High Energy Ratings to 12 J and Current to 4 A

Ametherm announced a new series of UL-approved circuit protection thermistors with industry-high energy and steady state current ratings for inrush current limiting in power supplies from 50 W to 200 W, 1/8 HP motors and small pumps, lighting, and audio charging stations for portable consumer devices.

The new SL08 series thermistors released this month feature maximum received energy ratings from 8 J to 12 J and handle steady state currents up to 4 A. The devices offer a wide range of resistance values from 2.5 Ω to 220 Ω, dissipation constants from 5.2 mw/°C to 90 mw/°C, and thermal time constants down to 8 s. The thermistors can handle body temperatures up to 158 °C at 100% of their maximum current rating.

Offering diameters from 7.5 mm to 9.0 mm and low profiles down to 2.8 mm, SL08 series devices provide designers with a more compact and cost-effective alternative to combining a power resistor, relay, and timer on one circuit to achieve the same functionality.

“From power supplies to the charging of portable media players, our SL08 thermistors provide designers with the high current protection they require without sacrificing board space,” said Eric Rauch, president and CEO at Ametherm. “It’s the most cost-effective and simple way to limit inrush current and increase reliability.”

SL08 thermistors are available direct from Ametherm or through distributors such as Mouser, Digi-Key, Newark element14, and Farnell. Samples and production quantities of the devices are available now, with factory lead times of four to five weeks. Volume pricing for U.S. delivery starts at $0.20 per piece.

For more information or to request a sample, visit

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