Patent ID: 7821249
Filing Date: 2010-10-26
Classification: G01R,H03K

Abstract:
1. A phase difference measuring device characterized by comprising: a plurality of first phase difference measuring circuits formed in a row; and first phase difference conversion circuits each connected between adjacent first phase difference measuring circuits, wherein said first phase difference measuring circuit receives a first signal and a second signal, respectively gives the first signal and the second signal a first delay amount and a second delay amount cumulatively a plurality of number of times, and, whenever giving the delay amounts, compares phases of the first signal and the second signal given the delay amounts, thereby determining which one of the phases leads the other, and said first phase difference conversion circuit receives the first signal and the second signal input to said first phase difference measuring circuit in a preceding stage, respectively gives the first signal and the second signal a first total delay amount as a total of the first delay amounts and a second total delay amount as a total of the second delay amounts given by said first phase difference measuring circuit in the preceding stage, and outputs the first signal and the second signal to said first phase difference measuring circuit in a succeeding stage.