A novel high-transconductance operational amplifier with fast setting time

Output setting time of operational amplifier consists of output large-signal setting time and output small-signal setting time. In order to increase the output setting time, it is necessary to increase both the slew rate and the gain-bandwidth product at the same time. In this paper, an operational amplifier structure is designed which can increase SR and GBW. The GBW of the whole operational amplifier is increased using transconductance multiplication technology. Dynamic bias current controlling technology is utilized in the input stage. Thus, the additional current source can enter the circuit of whole operational amplifier at large-signal input and provide the extra conversion current to enhance SR.