A DC-DC converter includes a switch capacitor converter core (101)； a switch driver (103) connected with the switch capacitor converter core (101)； a switch signal router (105) connected with the switch driver (103)； a gain selection decoder (107) connected with the switch signal router (105)； a gain controller (109) connected with the gain selection decoder (107)； an input adjusting device (111) connected with the gain controller (109)； an output adjusting device (113) connected with the gain controller (109)； and a clock generator (115) connected with the switch signal router (105), the gain controller (109) and the output adjusting device (113).
