Patent ID: 8102156

Claim:
A differential amplifier circuit, comprising: a first input transistor including a control electrode serving as a non-inversion input terminal; a second input transistor including a control electrode serving as an inversion input terminal, said second input transistor constituting a difference pair with the first input transistor; a bias current generation circuit section configured to generate a bias current flowing to the first and second input transistors; and an offset adjustment circuit section configured to adjust an input offset voltage appearing at said input terminals, said offset adjustment circuit section having an adjustment resistance formed from a first variable resistance inserted into a first current route connecting to the first input transistor, and a second variable resistance inserted into a second current route connecting to the second input transistor; wherein said bias current generation circuit section changes the bias current in accordance with a change in a value of the adjustment resistance and said bias current generation circuit section comprises: a bias current generation use resistance configured to change a value of its own resistance in proportion to a change in a value of the adjustment resistance; a current control circuit configured to control a current flowing to the bias current generation use resistance so that a voltage drop in the bias current generation use resistance becomes a prescribed amount; and a proportional current generation circuit configured to generate a current as a bias current in proportion to the current flowing from the current control circuit to the bias current generation use resistance.