| 摘要 |
PROBLEM TO BE SOLVED: To provide a drive control technology of a two-phase brushless motor, in which noise can be suppressed by limiting the r.p.m. of the motor through duty control, without lowering the driving efficiency. SOLUTION: Among a first counter for measuring the rotational period of a rotor by counting the clock signals, and second and third counters for counting the count of the first counter with a clock of a different frequency, rising of a duty control pulse is determined by the output from a counter operating with a clock of higher frequency, and falling of the duty control pulse is determined by the output from a counter operating with a clock of lower frequency. |
