| 摘要 |
PROBLEM TO BE SOLVED: To provide a skew measuring circuit capable of accurately measuring skew between differential output signals. SOLUTION: Differential output signals A, B are input in comparators a1 and b3 and compared with comparison reference voltages Vrefa, Vrefb and converted to pulse waves a, b. The pulse waves a, b are input in f-v conversion circuit a5, b6 and converted to voltages Va, Vb proportional to respective pulse widths ta, tb. A comparison reference voltage Vrefb is generated by a voltage generation circuit b8 so that the voltages Va and Vb become equal. By measuring the skew of the pulse waves a, b at the time of coincidence of the voltages, the skew between the differential output signals is measured. COPYRIGHT: (C)2005,JPO&NCIPI
|
