Digital phase control circuit including an auxiliary circuit

In a digital phase control circuit including a controllable oscillator having a control input;

• a programmable first divider having first and second inputs, said first input being coupled to the output of said oscillator;
• a reference frequency source comprising a second divider having an input;
• a phase discriminator having first and second inputs coupled to the outputs of said programmable first divider and said second divider respectively, said phase discriminator further having output means;
• and means coupling the output means of said phase discriminator to the control input of said controllable oscillator, the frequency of said oscillator being controlled in a direction determined by the direction of the phase deviation between the signals applied to the first and second inputs of said phase discriminator and compared therein;
• the improvement comprising:
• an auxiliary circuit having input means coupled to the output means of said phase discriminator, a first output coupled to the input of said second divider comprising said reference frequency source and a second output coupled to the second input of said programmable first divider, said auxiliary circuit generating a first synchronizing signal at the input of said second divider when the phase difference between the signals at the outputs of said programmable first divider and said second divider is in one direction and generating a second synchronizing signal at the second input of said programmable first divider when the phase difference between the signals at the outputs of said programmable first divider and said second divider is in the opposite direction thereby setting either said programmable first divider or said second divider, respectively, to a predetermined initial phase position, the divider set to said predetermined initial phase position being maintained in said position until the other divider reaches its predetermined initial phase position.