Abstract
Keywords:
Intelligent Power Switches (IPS), I-t Curve, On state resistance of IPS, Thermal circuit, Thermal shutdown
Abstract
This paper proposes an algorithm to generate I-t curve of an IPS from its simplified model. The model uses electrical and thermal characteristics of IPS like its on resistance (RON), thermal resistances (Rth) and capacitances (Cth) of its thermal circuit and its thermal tripping/shutdown temperature (TSHUTDOWN). I-t curves are extremely important for selection of an IPS for a particular load and wire in automotive industry. If only the IPS can sustain the load current and can protect the wire in case of a fault, it can be used for the application. This evaluation can be easily performed with the help of IPS I-t curve. The I-t curve generated using this algorithm is compared with that provided by the company (in application note) for some IPS. An application example using the I-t curve is also described. Finally the limitation of the model is mentioned and its effect is discussed with the help of the application example.