Ultrasonic diagnostic apparatus

An ultrasonic diagnostic apparatus for use with a subject, comprising:

• an ultrasonic probe including a plurality of ultrasonic transducers arranged in a predetermined arrangement, for generating and transmitting ultrasonic waves into the subject, receiving the ultrasonic waves reflected in the subject, and generating signals from respective ultrasonic transducers, based on the reflected ultrasonic waves;
• a delay control circuit coupled to said ultrasonic probe, for performing at least one of delay time control and phase control on the signals, to generate a display of the subject, said delay control circuit including
• a delay line including a predetermined number of delay control blocks coupled in series using at least one of external input and external output terminals of each of the delay control blocks, the delay control blocks including sub-delay line circuits with at least one of internal input and internal output terminals coupling the sub-delay line circuits in series, each sub-delay line circuit including a plurality of series-coupled delay elements and a plurality of delay taps coupled to respective points between or at first and second ends of the series-coupled delay elements, the first and second ends being coupled to the internal input and internal output terminals, respectively, and each of the delay elements providing a predetermined unit amount of delay, and
• a plurality of matrix switches coupled to the delay taps and to receive the signals, to select a group of cyclically adjacent delay taps, said group being determined based on a frequency of said ultrasonic probe, to delay said signals by respective predetermined amounts of delay based on the group selected.