Detected signal processing device for rotating sensor and detected signal outputting method therefor

摘要

The rotation of a rotating magnet is detected by magnetic sensors. The rotational speed is detected from pulse signals detected by magnetic sensors, and the rotational direction thereof is detected from the difference in the way of making a shift in phase. Signals different in pulse width are generated according to the rotational direction. A signal selection circuit outputs a corresponding pulse signal with timing for the rotational speed. A rotational speed determining circuit outputs a decision signal Sf of a high level when the rotational speed reaches a predetermined speed. When a self-diagnostic circuit determines that the magnetic sensors have malfunctioned, a binary error code generating circuit generates an error signal Sg and a 4-bit error code signal Sh. When the signal Sf of the rotating magnet is brought to a high level, the signal selection circuit associates a signal corresponding to the rotational direction with data of "1" or "0" to output an error code signal and allows a current output circuit to output an output current Is.