VB326SP is a high voltage power integrated circuit made by ST using the STMicroelectronics VIPower™ M1-3 technology, with vertical current flow power darlington and logic level compatible driving circuit. The enable pin allows to externally block the switch when the input is on. Built-in protection circuit for coil current limiting and collector voltage clamping allows the device to be used as smart, high voltage, high current interface in advanced electronic ignition system. If the input signal from the micro happens to remain high, the device protects itself against over-heating by forcing collector current to smooth decrease (low voltage clamp feature) and no undesidered spark occurs (see figure 4).