A digital clock multiplier (DCM) circuit including: a plurality of power amplifier (PA) rows, wherein each PA row comprises a plurality of cascade switched capacitor power amplifiers (SCPA) unit cells configured to: receive a phase shift of a driving clock phase; and one or more processors configured to: disable of one or more of the plurality of cascade SCPA unit cells based on a frequency of the phase shift; generate an output signal for each of the cascade SCPA unit cells; and combine the output signal for each of the cascade SCPA unit cells to generate an PA row output signal.