Abstract: A novel on-state open load detection circuit for intelligent high side power switch are presented based on BCD process. By using a double decision circuit, the problem of excessive voltage drop and small current detection error caused by traditional detection method is solved, the accuracy and reliability of open load detection are improved, and low threshold current detection of 1mA~10mA can be achieved. The Cadence Spectre simulation shows that with a threshold current of 3 mA, the open load detection accuracy is 98%. At a supply voltage of 24V, the charge pump output voltage is 27.67V, the charging time is 16.89μs, and the discharge time is 20.3μs. The switching time of this intelligent high-edge power circuit is far less than that of the same type of infineon products around 100μs.