CLOCK SELECTION CIRCUIT AND CLOCK DATA RECOVERY CIRCUIT EQUIPPED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To eliminate glitch attributed to output switching of a clock selection circuit.

SOLUTION: A clock selection circuit is provided with two clock selection parts 11a and 11b for receiving a plurality of clock signals which are deviated in phase from each other and selectively outputting one or more signal from among the clock signals, a clock switch part 12 for selecting between the clock selection parts 11a and 11b and outputting a clock signal outputted by the selected clock selection part, and a control unit 13 for controlling the clock selection parts 11a and 11b and the clock switch part 12. The control unit 13 instructs re-selection of the clock signal to one of the two clock selection parts 11a and 11b which is not selected by the clock switch part 12 and designates the clock switch part 12 to switch outputs after instruction.

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