Patent ID: 7592868

Claim:
A rail-to-rail amplifier for amplifying an analog signal from a digital-to-analog converter comprising: a first differential input section comprising an n-channel transistor pair; a second differential input section comprising a p-channel transistor pair; a first current supply, disposed between said second differential input section and a high voltage side first supply line, for supplying current from said first supply line to said second differential input section; a current controller for a second input section, disposed between said first current supply and said second differential input section, for controlling the current supply from said first current supply to said second differential input section in accordance with digital data at a predetermined bit position in input digital data to said digital-to-analog converter; a second current supply, disposed between a low voltage side second supply line and said first differential input section, for supplying current from said first differential input section to said second supply line; and a current controller for a first input section, disposed between said second current supply and said first differential input section, for controlling the current supply from said first differential input section to said second current supply in accordance with digital data at a predetermined bit position in input digital data to said digital-to-analog converter.