Patent ID: 7688134
Filing Date: 2010-03-30
Classification: H03F

Abstract:
1. A transimpedance amplifier comprising: a feedback circuit having two or more extreme frequencies, said feedback circuit having a filter characteristic which is flat with respect to frequencies in a frequency region not more than a smallest extreme frequency among the extreme frequencies, is flat with respect to frequencies in a frequency region not less than a largest extreme frequency among the extreme frequencies, and has at least one negative inclination portion with respect to frequencies in a frequency region between the smallest and largest extreme frequencies; and an amplifier connected to said feedback circuit; the largest extreme frequency of said feedback circuit being identical to a peaking frequency of said amplifier, wherein said feedback circuit is the feedback circuit having two terminals, said feedback circuit being formed of a plurality of resistances and at least one capacitance, said resistances being connected in parallel between said two terminals, said resistances being divided into two or more resistance groups, and said at least one capacitance being connected between respective dividing points of said resistances.