| 摘要 |
PURPOSE:To obtain a DC voltage less in pulsation and short in transient response time by selecting the DC output voltage among plural frequency-voltage converters according to the rotating speed of a rotating body. CONSTITUTION:A pulse signal converting circuit 12 inputs two-phase pulse signals EP1 and EP2 from a rotation detector 1 and outputs pulse signals EP31- EP34 which have specific mutually different multiplication frequency and pulse widths. Then, they are converted into DC voltages + or -E04-+ or -E04 by frequency- voltage converters 11a-11d and switch signals EP60-EP63 are obtained from a switch signal generating circuit according to the levels of the DC voltages to conrol an output switch circuit 15, thereby selecting and outputting one of DC output voltages of the converters 11a-11d according to the rotating speed of the rotating body. Thus, a DC voltage obtained by converting a pulse signal having a low frequency and a short pulse width when the rotating body rotates fast or a DC voltage obtained by converting a pulse signal having a high frequency and a short pulse width in slow rotation are selected to obtain the DC output voltage which has less pulsation and a short transient response time. |
