| 摘要 |
PURPOSE:To ensure the stable peak detection regardless of the level of the input signal of a peak detecting circuit by actuating plural stages of clamping diodes with an input of a high level and just a signal stage of the clamping diode with an input signal of a low level respectively through the peak detecting circuit. CONSTITUTION:A peak detecting circuit 13 differentiates an input signal A by a differentiating circuit consisting of a capacitor C5 and a resistance R6 and clamps it for peak detection. In this case, clamping diodes D3-D6 function as a large resistance to the signal A when this signal A has a comparatively low level. Therefore the diodes D3 and D4 work just by one stage. While the diodes D3-D6 function as a small resistance for the signal A when it has a high level. Thus diodes D3-D6 work by two stages. This circuit ensures the accurate peak detection despite a high level of the signal A. |
