A suitable part can be selected from the specifications and the protective-threshold current-range chart provided in our catalog or on the Murata website. For the above example, a POSISTOR® is selected that withstand up to 20 V between -10°C and 60°C. The Hold Current indicates the maximum current through the POSISTOR® where it functions like a 4.7 Ω resistor (un-tripped state). It is specified for 155 mA at 25 °C and 100 mA at 60°C. If the current through the POSISTOR® exceeds the trip current (330 mA at 25°C or 400 mA at -10°C), the POSISTOR® will be tripped and it resistance will be high. Within the Protective threshold current range, the part may or may not be tripped. The POSISTOR can withstand up to 5000 mA maximum current.