TDK Corporation (TSE:6762) has developed the J404, the world's first* surface-mountable inrush current limiter (ICL) based on PTC (positive temperature coefficient) technology. Designed for DC voltages of up to 500 V and AC voltages of up to 350 V, the device (order number B59404J0170A062) automatically and intrinsically limits excessive currents in applications such as DC links and charging devices in electromobility.

High-power loads are a major stress factor when fuses and components are switched on, as they cause very high currents to flow. To avoid this, TDK offers ceramic EPCOS inrush current limiters, based on NTC and PTC thermistors – a strong duo when used in combination.

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.
When power is first applied to electronic devices such as switching power supplies and inverters, an instantaneous current with an abnormally high peak will flow through them.<br>
This is known as “inrush current” and if not addressed, can lead to problems such as semiconductor element failure or reduced service life of smoothing capacitors. However, our inrush current limiting NTC thermistors can provide protection against this phenomenon to prevent such undesirable effects.

One of the properties of PTC thermistors is that when an excessively large current flows, they generate heat by themselves and become highly resistive. With this property, they are used as overcurrent protection devices. This article describes applications for inrush current limiting, overcurrent protection and telecom application.