A single-inductor dual-output (SIDO) step-down converter with continuous conduction mode (CCM) control is proposed for high efficiency system-on-a-chip (Soc) integration. The cross regulation in steady-state output voltage ripple, which is rarely mentioned, is effectively reduced as well as in transient response. The low-voltage energy distribution controller (LV-EDC) circuit guarantees good voltage regulation and low output voltage ripple simultaneously. In addition, within the allowable output voltage ripple, the automatic energy bypass (AEB) mechanism can reduce the number of energy delivery path to decrease the switching loss. Two outputs are operated with the load-dependent energy path for improving the power conversion efficiency. The chip fabricated in 55 nm CMOS achieves 91 % peak efficiency, low output voltage ripple, and excellent load transient response.