HIGH SLEW RATE OPERATIONAL AMPLIFIER AND OPERATING METHOD THEREOF

A high slew rate operational amplifier including an input terminal, an output terminal, and at least one slew-rate enhancing circuit is disclosed. Each slew-rate enhancing circuit includes a first stage enhancing unit and a second stage enhancing unit. The first stage enhancing unit is coupled between the input terminal and the output terminal. The first stage enhancing unit and the second stage enhancing unit are coupled. The slew-rate enhancing circuit has a threshold voltage and the threshold voltage is related to the size of the first stage enhancing unit. When the threshold voltage is driven, the slew-rate enhancing circuit will rapidly start the second stage enhancing unit to perform a slew rate compensation on the high slew rate operational amplifier.