Patent attributes
A transmit pulser includes an H-bridge of four transistors. First and second transistors of the H-bridge connect with a first electrode of a transducer element, and third and fourth transistors of the H-bridge connect with a second electrode of the transducer element. A differential receive amplifier connects with the first and third transistors. First and second diode clamps connect with the first and third transistors, respectively, and the inputs to the differential receive amplifier. The second and fourth transistors connect to a same power or voltage source, imposing a same voltage in either a forward or a reverse direction. By using matched transistor pairs (e.g. first and third matched pair and second and fourth matched pair), symmetrical transmit waveforms are generated. Symmetrical transmit waveforms allow for using phase inversion or phase differences between transmit waveforms for imaging, such as for harmonic imaging of tissue. The spectral content of symmetrical waveforms is narrower or includes less harmonic information.