Patent ID: 7564310

Claim:
An amplifier comprising: an operational amplifier comprising a first input terminal receiving a first input signal, a second input terminal receiving a second input signal, and an output terminal outputting an output signal; a first resistor circuit connected between the second input terminal and a first node; a first fuse box connected between the first node and the output terminal of the operational amplifier; a second resistor circuit connected between the second input terminal and a second node; and a second fuse box connected between the second node and a first terminal for receiving a first voltage, wherein the first fuse box comprises: a plurality of first resistors connected in series between the first node and the output terminal of the operational amplifier; and a plurality of first fuses connected in parallel with the first resistors, respectively, wherein the second fuse box comprises: a plurality of second resistors connected in series between the second node and the first terminal; and a plurality of second fuses connected in parallel with the second resistors, respectively.