Control Device

To provide a control device capable of calculating a cam phase equal to an actual cam angle even when a corresponding cam angle signal detection range is exceeded by changing a cam phase by a variable valve mechanism. In addition to the conventional cam angle measuring function, a cam angle measuring means for advancing or retarding beyond a cam angle measurement reference position, and a means for determining that the cam angle signal advances or retards beyond the cam angle measurement reference position are provided. By switching the cam angle measuring function according to a determination result as to whether the cam angle signal exceeds the cam angle measurement reference position, it is possible to improve the time resolution of the angle measurement while maintaining the cam phase change amount at the same wide angle as the conventional one.