An intelligent power IC with reverse battery protection for fast-switching high-side solenoid drive

A highly reliable and fast-switching intelligent power IC (IPIC) for a high-side solenoid drive is described. There are two main features in this IPIC. The first feature is a built-in reverse battery protection method that can be used in both 12-V battery systems and 24-V battery systems in large vehicles. This protection is accomplished by using a high-voltage MOSFET to suppress a forward current of a parasitic diode in the reverse battery condition. The other notable feature is a device isolation structure and driving method using two sets of pull-down circuits to reduce the turn-off time for the inductive load current. The turn-off time for the inductive load is reduced to two-thirds that of a conventional IPIC. This is achieved by increasing the absolute value of the sustained negative output voltage from -18 to -34 V. This IPIC also has over-current protection, over-heating protection, over-voltage protection, and a self-diagnostic function as well as the conventional IPIC function. It is useful for high-side solenoid drivers frequently used in automotive electronics.