Method of driving two-dimensional array ultrasonic probe, and ultrasonic diagnostic apparatus

An ultrasonic diagnostic apparatus comprising:

• N voltage amplifiers for amplifying signal voltages from transducers in a two-dimensional array ultrasonic probe;
• N voltage-to-current converters for converting voltages output from said voltage amplifiers into current signals;
• a current addition circuit having N inputs supplied with said current signals, and having M (<N) outputs for outputting additive current signals obtained by dividing the N inputs into M (<N) groups and adding current signals in respective groups;
• M current-to-voltage converters for converting said additive current signals into voltage signals;
• and
• a beamformer for conducting reception beamforming using said voltage signals.

An ultrasonic diagnostic apparatus comprising:

• N voltage amplifiers for amplifying signal voltages from transducers in a two-dimensional array ultrasonic probe;
• N multiplied by k (k≧2) voltage-to-current converters for converting voltages output from said voltage amplifiers into current signals;
• k current addition circuits each having N inputs supplied with said current signals, and having M (<N) outputs for outputting additive current signals obtained by dividing the N inputs into M (<N) groups and adding current signals in respective groups;
• M multiplied by k current-to-voltage converters for converting said additive current signals into voltage signals;
• and
• k beamformers for conducting reception beamforming using said voltage signals.