a square wave with a 50 % duty cycle which has frequency twice that of an input square wave also having a 50 % duty cycle is obtained by generating from the incoming square wave two waveforms having 75 % duty cycles with the two waveforms 180 ° out of phase with each other . the two waveforms are combined in an anding operation to obtain an output waveform which is a square wave with twice the frequency of the incoming square wave . in similar fashion , using additional similar circuits and gating , tripling is possible .