Patent ID: 7235981

Claim:
An impedance conversion circuit comprising: a first voltage-to-current converter and a second voltage-to-current converter supplied with differential input signal voltages; an inverting amplifier; and a third voltage-to-current converter for feedback, wherein a first resistance and a second resistance are connected in series with each other between an input terminal and an output terminal of said inverting amplifier, an output terminal of said first voltage-to-current converter is connected to the input terminal of said inverting amplifier, an output terminal of said second voltage-to-current converter is connected to a connection node of said first resistance and said second resistance, the output terminal of said inverting amplifier is connected to an input terminal of said third voltage-to-current converter, an output terminal of said third voltage-to-current converter is connected to an input terminal of said first voltage-to-current converter, and an impedance is connected between said connection node and a ground.