New Surge-Gard™ InRush Current Limiting NTC Thermistors from API Technologies Reduce Circuit Failures

API Technologies has announced the introduction of their latest development in NTC thermistors, Surge-Gard™ inrush current limiting devices. Designed to limit the inrush current that occurs when power is applied to a system, Surge-Gard NTC thermistors help reduce circuit failures and lower rectifier costs by reducing required peak forward surge current ratings. Featuring steady state current ratings ranging from 1 to 36 amps and resistance values from 0.5Ω to 220Ω, Surge-Gard is manufactured using specially formulated metal oxide ceramic materials that allow the thermistors to suppress high inrush current surges.

“Surge-Gard inrush current limiting NTC thermistors are ideal for switching power supplies where the low impedance of the charging capacitor exposes the diode bridge rectifier to an excessively high current surge at turn-on,” said Larry Howanitz, Vice President, EIS & Sensors, API Technologies. “They offer maximum current protection when the power supply is turned on, allowing the design engineer to select lower peak current rated diode bridge rectifiers for use in the switching power supply.”

API offers fast prototyping of custom designs that utilize the new Surge-Gard as well as a wide variety of lead gauges and configuration. API’s in-house design capabilities, diagnostic testing and world-class manufacturing offers application-specific products that lower costs and reduce time to market.

For more information on the new line NTC thermistors, visit