| 摘要 |
PURPOSE:To prevent leakage and radiation of noise to other circuit by synthesizing a noninverting output of a 1st logic circuit and an inverting output of a 2nd logic circuit and synthesizing the inverting output and the noninverting output of both the logic circuits and using the two synthesis signals as two input signals to a differential amplifier. CONSTITUTION:An in-phase spike component is generated to terminals U, D of ON/NOR gates 6, 7 and an opposite phase spike component is generated to terminals U', D' being opposite terminals of a balance output. Thus, the outputs at the terminals U, D' and the outputs at the terminals D, U' are synthesized to cancel the spike noise component. Since a signal not including the spike component is inputted to an amplifier 8, no noise component appears at an output terminal of a phase comparator 51. Thus, a signal with a level lower by the spike noise component, that is, only the required signal component appears at the output terminal. |
