Patent ID: 8149055

Claim:
A semiconductor integrated circuit device comprising: an amplification portion having a first transistor configured to inversely amplify an input signal inputted to a gate and output the inversely amplified input signal from a drain; and a cascode current source including the first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, and an impedance element, the first transistor including a gate and a drain between which the impedance element is connected, and a source connected to a drain of the second transistor, the second transistor including a gate connected to a gate of the fourth transistor and a source connected to a reference potential point to supply a bias current to the first transistor, the third transistor including a drain which is supplied with a current from a current source and is connected to the gate of the second transistor, and a source connected to a drain of the fourth transistor, the fourth transistor including a source connected to a reference potential point, the fifth transistor having same characteristics as the first transistor, and including a gate connected to a gate of the third transistor and to a drain of the fifth transistor, and a source connected to a drain of the sixth transistor, the sixth transistor having same characteristics as the second transistor, and including a gate connected to the gate of the fourth transistor and a source connected to a reference potential point to supply a bias current to the fifth transistor.