A pre-emphasis circuit and methods are provided. The circuit includes a
first amplifier and a second amplifier. The first amplifier is operable
to amplify a signal using a first amplifier current, and the second
amplifier is operable to amplify a delayed version of the signal using a
second amplifier current. The pre-emphasis circuit further includes a
logic circuit operable to change a pre-emphasis ratio of the pre-emphasis
circuit including switching off one or more of first driver cells of the
first amplifier and switching on a corresponding one or more of second
driver cells of the second amplifier, such that a total current
consumption of the first amplifier and the second amplifier remains
substantially constant.