Patent ID: 8451155

Claim:
A transmission circuit for use with an ultrasonic probe including an ultrasonic transducer, said transmission circuit comprising: a high voltage current digital to analog converter (DAC) configured to output a drive current to the ultrasonic transducer to transmit and receive ultrasound, wherein the high voltage current DAC comprises a high voltage current mirror circuit including: a first transistor and a plurality of second transistors corresponding to the first transistor, wherein at least one current flows from at least one of the second transistors to an output line; a positive-side high voltage current mirror circuit connected to a positive voltage and configured to output a positive drive current; and a negative-side high voltage current mirror circuit connected to a negative voltage; and a waveform generator configured to output a control signal to the high voltage current DAC with a predetermined timing to output the drive current with a desired magnitude from the high voltage current DAC.