Disclosed is a drive integrated circuit for controlling a traffic light. The drive IC comprises an input end and an output end, an input low-voltage control circuit, a gain control circuit, a driving circuit, an impedance loop and a phase detection circuit. The input low-voltage control circuit connects to the input end of the drive IC, and receives a first external signal. The gain control circuit connects to the input low-voltage control circuit. The driving circuit connects to the gain control circuit. The impedance loop connects to the input end to detect whether the traffic light is damaged. The phase detection circuit connects to the input end to detect a phase difference of the driving signal. By integrating circuits having different detection and control functions in one single chip, the cost of the drive IC decreases and the traffic light can have a less thick structure.