| 摘要 |
<p>The present invention aims to provide a fiber optic receiving circuit which can obtain a sufficient frequency band even if a junction capacity (CJ) of a photo diode (4) is large, wherein a voltage dividing ratio of said voltage dividing circuit (11), a capacity value of a capacitor (CO), a junction capacity value of a photo diode (4), and and an open loop gain of an amplifier (1) are determined so that current, which flows in the capacitor (Co), cancels current, which flows in a junction capacity (CJ) of the photo diode (4) and causes frequency deterioration, and the junction capacity (CJ) of the photo diode (4), which causes the frequency deterioration, does not relate to an output voltage of the amplifier (1), thereby obtaining a flat gain characteristic over the broad range of the frequency band regardless of the junction capacity (CJ) of the photo diode (4). <IMAGE></p> |
