Leistungsstarke Lasten sind beim Einschalten für Sicherungen und Bauelemente ein großer Stressfaktor, da hierbei sehr hohe Ströme fließen. Um diese zu vermeiden, bietet TDK keramische EPCOS Einschaltstrom-Begrenzer auf der Basis von NTC- und PTC-Thermistoren, die auch kombiniert eingesetzt werden können.

TDK has an extensive lineup of inrush current limiting NTC thermistors available. This article describes various example applications of these products, used for ICL (inrush current limiting) purposes to easily and effectively suppress inrush current.

Varistors can be used as suppressors to protect devices and circuits from transient abnormal voltages including an ESD (electrostatic discharge) and a lightning surge. For protection from a relatively large surge current (100A to 25kA), leaded disk varistors and SMD disk varistors are suitable. For protection from a larger surge current (approximately 25kA or more), block varistors, and strap varistors are suitable.

SMD or chip varistors are voltage-dependent resistors based on ceramic multilayer technology. They are widely used to protect electronic circuits in consumer devices and telecom, industrial and automotive applications against transient overvoltages, such as electrostatic discharges (ESD) and surge transients.

Chip varistors have both surge absorption capabilities and noise suppressing effects.

TDK’s chip varistors in the AVR series, which are made with our own materials, feature high resistance to repeated surges. Products that substitute Zener diodes in compact devices such as solenoid valves and stepping motors, which are rapidly and frequently turned on and off, are also available.

NTC thermistors are heat-sensitive resistor elements of which resistance values rapidly decrease with rise of temperature. With this property, they are used as temperature protection devices for protecting circuits from overheating as well as temperature sensors.

Surge arresters are GDT (gas discharge tube) voltage protection devices. TDK offers a strong lineup of products with a variety of surge current capabilities ranging from lightning protection for power lines to lightning protection for signal lines.