Controlled power performance driver circuit

The circuit rapidly charges and discharges a load capacitor by sensing the direction of transients at an internal node of the circuit which is selectively isolated from a capacitive output node to produce significant load current during upward transients. In an embodiment of the invention, the circuit includes a driver device and first, second and third field effect transistors. The first transistor is connected between a voltage supply terminal and the driver device forming an internal node between the first transistor and the driver device and acts as a current source pulling up the internal node. The second transistor is connected between the internal node and an output node and is arranged to selectively isolate the internal node from the output node, with isolation increasing during a positive transient to allow maximum drive to the third transistor connected between the voltage supply terminal and the output node to produce increased output current. The second transistor is also arranged to minimize the isolation between the internal and output nodes during negative transients to rapidly discharge the output node.