| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical reception circuit for dealing with burst transmission that automatically corrects an amplifier offset voltage so as to eliminate the need for the adjustment. SOLUTION: Capacitors 4a, 4b couple a plurality of differential amplifiers 2, 3 in terms of AC(alternating current) that process an output signal of a photo diode 1 converting a received burst light into an electric signal in the optical receiver for dealing with burst transmission. A peak hold circuit 5a and a bottom hold circuit 6a respectively detect and hold a peak value and a bottom value of one output from the differential amplifier 2 placed before the AC coupling capacitors, a difference voltage between the hold voltages is given to a 1st input of the differential amplifier 3 via a capacitor 12a, a peak hold circuit 5b and a bottom hold circuit 6b respectively detect and hold a peak value and a bottom value of the other output from the differential amplifier 2, and a difference voltage between the hold voltages is given via a capacitor 12b to a 2nd input of the differential amplifier 3, where the difference voltages are summed. |
