| 摘要 |
PROBLEM TO BE SOLVED: To provide a phase difference detecting circuit capable of precisely detecting phase difference information by a simple configuration and to provide PLL circuit using the circuit. SOLUTION: Data sampled by a sampling clock which is twice the frequency of an input signal is classified into difference sample data e1 and detecting point sample data d1 on every other sample. Then, an edge concerning the input signal is detected (d3) from the two kinds of detecting point sample data in front and rear of successively inputted detecting point sample data d1. Phase difference between the input signal and the clock is detected through the use of difference sample data value e1 between the two kinds of detecting point sample data whose edges are detected by an edge detecting means and at least one detecting point sample data value (d2). |
