A method and apparatus for propagating charge through a sensor and implementation thereof is provided. The method and apparatus may be used to inspect specimens, the sensor operating to advance an accumulated charge between gates of the TDI sensor. The design implementation provides a set of values representing a plurality of out of phase signals, such as sinusoidal or trapezoidal signals. These out of phase signals are converted and transmitted to the sensor. The converted signals cause the sensor to transfer charges in the sensor toward an end of the sensor. Aspects such as feed through correction and correction of nonlinearities are addressed.
