| 摘要 |
PROBLEM TO BE SOLVED: To perform reliable and stable correction drive by accurately determining a rotating state of a stepping motor. SOLUTION: In a stepping motor control circuit, a detection unit for detecting a rotating state of a stepping motor 102 is divided into a first section T1 immediately after the drive by a main drive pulse P1, a second section T2 subsequent to the first section T1, and a third section T3 subsequent to the second section. When the stepping motor 102 is driven by the main drive pulse P1, if a rotation detecting circuit 108 and a detection-time comparison discriminating circuit 109 detect an induction signal VRs, exceeding a first reference threshold voltage Vcomp1, in the first section T1 and in the second section T2 and when they are unable to detect the induction signal VRs, exceeding a second reference threshold voltage Vcomp2 lower than the first reference threshold voltage Vcomp1, in the third section T3, a control circuit 106 performs pulsing-up of the main drive pulse P1 while driving the stepping motor by a correction drive pulse P2. COPYRIGHT: (C)2010,JPO&INPIT |
