Patent ID: 8570815

Claim:
A semiconductor device comprising: a sense amplifier; a first power supply line supplying a high-potential voltage equal to or higher than a first power supply voltage to said sense amplifier; a second power supply line supplying a second power supply voltage higher than said high-potential voltage; a first transistor, a second transistor, and a third transistor including respective drain terminals and source terminals connected between said first power supply line and said second power supply line; and a first control circuit, a second control circuit, and a third control circuit applying a first control signal, a second control signal, and a third control signal, respectively, to gate terminals of said first transistor, said second transistor, and said third transistor; wherein said second control circuit and said third control circuit including a first operational amplifier and a second operational amplifier, respectively; said first control signal and said second control signal comprise digital signals including a first differential voltage between said first power supply voltage and a ground voltage and including a potential voltage that is selectively changeable to two values represented by said first power supply voltage and said ground voltage, respectively; said third control signal comprises an analog signal including a second differential voltage smaller than said first differential voltage and including a potential voltage that is changeable between said first power supply voltage and said ground voltage, respectively; said first control circuit generates said first control signal to render said first transistor electrically conductive or nonconductive; said second control circuit generates said second control signal which is a digital signal converted from an analog signal detected by said first operational amplifier to render said second transistor electrically conductive or nonconductive; and said third control circuit outputs an analog signal detected by said second operational amplifier as said third control signal to render said third transistor electrically conductive or nonconductive.