Amplifier circuit and feedback circuit

摘要

An amplifier circuit whose frequency response has almost no soft knee characteristic or no peak when inverting input capacitance Csin varies and when feedback capacitance Cf is a fixed value of small capacitance, and a feedback circuit is provided. The amplifier circuit includes a plurality of amplifiers each of which negative feedback is provided to and which are connected in series, and a feedback means (feedback circuit) which is connected to an output side of an amplifier near output of the amplifier circuit and an input side of an amplifier near input of the amplifier circuit. These amplifiers are ones in the plurality of amplifiers. One or odd numbers of amplifiers in the plurality of amplifiers are inverting amplifiers.

主权项

1. An amplifier circuit comprising:
a plurality of amplifiers which are connected in series, the plurality of amplifiers being either three or more odd number of inverting amplifiers, or a combination of one or more odd number of inverting amplifier and one or more non-inverting amplifiers, each of the inverting amplifiers and the non-inverting amplifiers including an amplifier unit to which a negative feedback circuit is connected, the negative feedback circuit including a feedback resistor that is directly connected to an input and an output of the amplifier unit; and a feedback circuit which provides feedback from an output of an amplifier that is in a side of output of the plurality of amplifiers to an input of an amplifier that is in a side of input of of the plurality of amplifiers, wherein the feedback circuit provides negative feedback from an output of the amplifier circuit to an input of the amplifier circuit.