| 摘要 |
PROBLEM TO BE SOLVED: To provide a reception circuit with a simple configuration capable of automatically setting a strobe point to an optimum phase.SOLUTION: The circuit includes: a decision feedback type equalization circuit (DFE) 42 for acquiring at a strobe point; a controlling part (controller 4)6 for replaying clock data and controlling an acquisition voltage level at DFE at the same time; and a phase shifter PI43 for changing a phase of the strobe point. The controlling part detects both extreme phases of a phase range that can be correctly acquired at a first voltage level, calculates an intermediate phase, detects a margin voltage level, which is one of both extreme phases, calculates an inclination of a linear line connecting the other of both extreme phases and the margin voltage level, detects an intermediate voltage level within a voltage range in the intermediate phase, calculates a phase difference between the intermediate phase and a phase which is at the same voltage level as the intermediate voltage level on a linear line that passes through the intermediate phase and has the calculated inclination in an eye pattern, and sets a strobe point to a phase shifted from the intermediate phase by an amount of the phase difference.SELECTED DRAWING: Figure 6 |
