Integrated fuse delivers compact overvoltage protection

TDK EPCOS ThermoFuse NT14 and NT20 series of fuse protected varistors provide compact overvoltage protection and a footprint that fits into existing circuit board layouts. NT14 series (disk diameter 14mm) absorb maximum surge currents with an 8/20-μs pulse of 6kA at rated voltages of between 130VRMS and 680VRMS. NT20 series (disk diameter 20mm) has a surge current capability with an 8/20-μs pulse of 10kA at rated voltages of between 130VRMS and 750VRMS. Devices deliver a maximum energy absorption of up to 220J and 480J for 2ms, respectively. Both series are available in 2-leaded and 3-leaded types, with the third lead used to monitor whether the fuse has been activated.