Design of rail-to-rail operational amplifier with offset cancelation in 90nm technology

This paper deals with the design of a rail-to-rail operational amplifier (OPAMP) for a digital-to-analog converter. To achieve a low input offset of the OPAMP, a digital offset cancelation method has been proposed and used. The offset voltage in the range from -1.4 mV to 1 mV can be achieved. The OPAMP and additional hardware were designed in 90nm CMOS technology.