ADJUSTING CIRCUIT FOR CORING THRESHOLD OF SIGNAL

摘要

PROBLEM TO BE SOLVED: To attain a prescribed characteristic by providing a differential stage that is controlled by a branch with a low/high gain and that has a branch providing an output signal so that a current of a symmetrical differential stage is selected to be a value corresponding to a maximum amplitude. SOLUTION: The circuit has a circuit including an asymmetrical differential amplifier stage having a low gain branch Q1 and a high gain branch Q2. The low gain branch Q1 is controlled by an input voltage and has a 1st load D1. Furthermore, the high gain branch Q2 has a 2nd load D2 with the same characteristic as that of the 1st load D1 and is controlled by a voltage corresponding to start of a reduction part. Then a 1st current 12 is given to the asymmetrical differential sage and the current corresponds to the end of the reduction part. Then a 1st branch Q3 controlled with the low gain branch Q1 is provided to a symmetrical differential stage and an output signal of the circuit is given thereto. A 2nd branch Q4 of the symmetrical differential stage is controlled with the high gain branch Q2 and the current of the symmetrical differential stage is set to a value corresponding to the maximum amplitude of the output signal.