Clock signal selecting apparatus and method that guarantee continuity of output clock signal

摘要

Provided are a clock signal selecting apparatus and method that can guarantee the continuity of an output clock signal. The clock signal selecting apparatus and method can synchronize the phases of at least two clock signals by continuously controlling the phases of the clock signals. Accordingly, even when an active clock signal and a standby clock signal have different frequencies, it is possible to guarantee the continuity of the output clock signal regardless of whether the clock signals are switched from one to another. In addition, it is possible to guarantee the stability of the output clock signal.