Abstract: A control circuit (115), a control method, a DC-DC converter and an electronic device are provided. The control circuit (115) is used to control the DC-DC converter to switch its operation modes. In the control circuit (115), whether mode of the DC-DC converter is to be switched is judged according to parameters of a first duration of an active duration and a second duration of an inactive duration. Comparison of analog values is prevented, and as a result, the use of the analog comparator is reduced, thus the influence of the semiconductor processes on designing a controller can be reduced.