| 摘要 |
PROBLEM TO BE SOLVED: To provide a phase detection device capable of improving the detection accuracy of a phase by using a sensor signal having a signal level corresponding to a rotational phase.SOLUTION: The phase detection device includes a signal selection part 4, a bias level generation circuit 2, and a phase information detection circuit 3. The signal selection part 4 selects one sensor signal among a plurality of sensor signals U1, V1, W1 having a signal level corresponding to the phase of a rotator as a selection sensor signal X. The bias level generation circuit 2 performs division with a ratio a:b between respective signal levels of a pair of sensor signals comprising the selection sensor signal X and another sensor signal to generate each bias level L,L. The phase information detection circuit 3 generates a threshold level Lv(n) corresponding to the phase of the rotator on the basis of each bias level L,L, and detects that the signal level of the selection sensor signal X reaches the threshold level Lv(n).SELECTED DRAWING: Figure 2 |
