The present invention provides a display system comprising a liquid crystal display (LCD) controller and an organic light emitting diode (OLED) driver circuit. The LCD controller can be a mono super twisted nematic (STN) and gray scale and color thin film transistor (TFT) controller. The LCD controller processes general format data and accordingly generates segment control signals and common control signals. The OLED driver circuit according to a general embodiment of the display system of the present invention comprises an OLED segment driver with a corresponding segment interface adopter processing the segment control signals from the LCD controller, and an OLED common driver with a corresponding common interface adopter processing the common control signals from the LCD controller. According to a further embodiment, the display system further comprises a drive strength selector controlling the drive strength in the OLED segment driver. The display system according to the present invention can also include a drive strength selector controlling the drive strength in the OLED common driver.