| 摘要 |
PURPOSE:To obtain an amplitude limiting circuit which delivers the zero-point cross information accurately, by securing the combination between the comparing circuit having the hysteresis characteristics and that having no hysteresis characteristics. CONSTITUTION:Input signal A sent from terminal 11 is supplied to comparing circuit 16 having no hysteresis characteristics virtually as well as to comparing circuit 12 having the hysteresis characteristics respectively. Here circuit 16 functions as a zero cross comparator to generate signal D; and circuit 12 delivers signal B which has no response to the input lower than a certain level and received the limitation of amplitude. Then signal D plus output signal E of signal B passed through level converting circuit 21 are supplied to pulse generator 31 to deliver signal F which corresponds to the phase difference of both signals mentioned above. Both signals F and E are supplied to FF circuit 41 to obtain output signal G. In this way, an amplitude limiting circuit, which has no response to the input lower than a certain level and also delivers the accurate zero-point cross information, can be obtained. |
