An integrated circuit is disclosed including a primary input for receiving an input voltage, a battery voltage input for receiving a battery voltage signal and an output for providing an output voltage higher than the battery voltage. First circuitry responsive to the input voltage is provided for turning off the output voltage responsive to an input over voltage condition. Second circuitry responsive to the battery voltage signal is provided for turning off the output voltage responsive to a battery over voltage condition. Third circuitry provides for over current protection.