| 摘要 |
<p>An integrating circuit (1) integrates an input signal. When an output from the integrating circuit (1) is input to an AC coupling circuit (2), only an AC component of the output is extracted. The AC component which passes through the AC coupling circuit (2) is waveshaped and coverted into a rectangular wave by a waveshaping circuit (3). The duty ratio of the waveshaped rectangular wave is detected by a duty ratio detecting circuit (4). A voltage corresponding to the duty ratio is then generated and fed back to the output of the AC coupling circuit (2) through a feedback circuit (5). As a result, a DC bias component is applied to the AC component which has passed through the AC coupling circuit (2). In this case, the voltage generated by the duty ratio detecting circuit (4) is controlled to coincide with the circuit threshold value of the waveshaping circuit (3), and a rectangular wave having a duty ratio of 50% is output from the waveshaping circuit (3).</p> |
