Transmit generator for controlling a multilevel pulser of an ultrasound device, and related methods and apparatus

Abstract

Circuitry for ultrasound devices is described. A multi-level pulser is described, which can support time-domain and spatial apodization. The multi-level pulser may be controlled through a software-defined waveform generator. In response to the execution of a computer code, the waveform generator may access master segments from a memory, and generate a stream of packets directed to pulsing circuits. The stream of packets may be serialized. A plurality of decoding circuits may modulate the streams of packets to obtain spatial apodization.

1 . (canceled) 
     
     
         2 . A method of controlling a pulser coupled to an ultrasonic transducer of an ultrasound device, the ultrasound device comprising a packet generator and a memory storing a plurality of master segments indicating a plurality of selectable reference voltages including a first master segment indicating a first reference voltage and a second master segment indicating a second reference voltage, the method of controlling the pulser comprising:
 selecting, with the packet generator, a subset of master segments including the first master segment and the second master segment from the plurality of master segments;   generating, with the packet generator and using the subset of master segments, an ordered succession of data packets at least in part by generating, from the first master segment, a first data packet in the ordered succession of data packets comprising a first value representing the first reference voltage and generating, from the second master segment, a second data packet in the ordered succession of data packets comprising a second value representing the second reference voltage;   transmitting the first and second data packets to the pulser;   in response to transmitting the first data packet to the pulser, setting the pulser to a first state corresponding to the first reference voltage; and   in response to the transmitting the second data packet to the pulser, setting the pulser to a second state corresponding to the second reference voltage.   
     
     
         3 . The method of  claim 2 , wherein the first data packet in the succession of data packets includes data identifying a duration of a pulse generated by the pulser. 
     
     
         4 . The method of  claim 2 , further comprising encoding the succession of data packets and decoding the succession of data packets prior to providing the succession of packets sequentially to the pulser. 
     
     
         5 . The method of  claim 2 , wherein the pulser includes a pull-up transistor and a pull-down transistor, and wherein the first data packet in the succession of data packets includes data identifying conductive states of the pull-up transistor and the pull-down transistor. 
     
     
         6 . An ultrasound device comprising:
 an ultrasonic transducer;   a pulser coupled to the ultrasonic transducer;   a memory storing a plurality of master segments indicating a plurality of selectable reference voltages including a first master segment indicating a first reference voltage and a second master segment indicating a second reference voltage;   a packet generator configured to select a subset of master segments including the first master segment and the second master segment from the plurality of master segments and generate, using the subset of master segments, an ordered succession of data packets at least in part by generating, from the first master segment, a first data packet in the ordered succession of data packets comprising a first value representing the first reference voltage and generating, from the second master segment, a second data packet in the ordered succession of data packets comprising a second value representing the second reference voltage;   encoding circuitry configured to encode the first and second data packets;   delay circuitry configured to generate a plurality of time-delayed versions of the first and second data packets subsequent to the encoding of the first and second data packets; and   decoding circuitry configured to decode the plurality of time-delayed versions of the first and second data packets.   
     
     
         7 . The ultrasound device of  claim 6 , wherein the ultrasound device comprises a handheld ultrasound probe and wherein the memory, ultrasonic transducer, and delay circuitry are on the handheld ultrasound probe. 
     
     
         8 . The ultrasound device of  claim 7 , wherein the encoding circuitry is on the handheld ultrasound probe. 
     
     
         9 . The ultrasound device of  claim 6 , wherein the ultrasound device is further configured to transmit one of the plurality of time-delayed versions of each of the first data packet and the second data packet to the pulser; and
 wherein the pulser is configured to be set to a first state corresponding to the first reference voltage throughout a first duration in response to transmitting the one of the plurality of time-delayed versions of the first data packet to the pulser and to a second state corresponding to the second reference voltage throughout a second duration in response to transmitting the one of the plurality of time-delayed versions of the second data packet to the pulser.   
     
     
         10 . The ultrasound device of  claim 9 , wherein the ultrasonic transducer is configured to generate an acoustic ultrasound waveform segment in response to setting the pulser to the first state, wherein the acoustic ultrasound waveform has a magnitude that is determined by the first reference voltage. 
     
     
         11 . The ultrasound device of  claim 9 , wherein the pulser comprises a first transistor and a second transistor, and wherein the first data packet comprises a value representing a first conductive state associated with the first transistor and a second conductive state associated with the second transistor; and
 wherein the first transistor is configured to assume the first conductive state and the second transistor is configured to assume the second conductive state based on the value.   
     
     
         12 . The ultrasound device of  claim 9 , wherein the pulser is a first pulser of a plurality of pulsers and the ultrasound device is configured to modulate the first data packet across the plurality of pulsers to obtain spatial apodization. 
     
     
         13 . The ultrasound device of  claim 9 , wherein the ultrasound device is configured to transmit first data packet and the second data packet serially. 
     
     
         14 . A method of controlling a plurality of pulsers coupled to a plurality of ultrasonic transducers, the method comprising:
 selecting two or more waveform segments from among a plurality of waveform segments with a packet generator, the two or more waveform segments comprising a subset of master segments from a plurality of master segments stored in a memory on a handheld ultrasound probe, wherein the plurality of master segments indicate a plurality of selectable reference voltages, and the subset of master segments include a first master segment indicating a first reference voltage and a second master segment indicating a second reference voltage;   generating, with the packet generator, a succession of packets based on the subset of master segments, wherein generating the succession of packets defines an order for the succession of packets and comprises:
 generating, from the first master segment, a first data packet in the succession of packets with the packet generator, the first data packet comprising a first value representing the first reference voltage; and 
 generating, from the second master segment, a second data packet in the succession of packets with the packet generator, the second data packet comprising a second value representing the second reference voltage; 
   concatenating the selected two or more waveform segments to form an input waveform, wherein concatenating the selected two or more waveform segments comprises concatenating the first and second data packets; and   providing the input waveform to a pulser of the plurality of pulsers coupled to the plurality of ultrasonic transducers.   
     
     
         15 . The method of  claim 14 , further comprising:
 generating a pulse with the pulser from the input waveform;   providing the pulse to an ultrasonic transducer of the plurality of ultrasonic transducers; and   generating an acoustic ultrasonic waveform with the ultrasonic transducer of the plurality of ultrasonic transducers based on the pulse.   
     
     
         16 . The method of  claim 14 , wherein the pulser of the plurality of pulsers is configured to provide a multi-level pulse to at least one ultrasonic transducer of the plurality of ultrasonic transducers. 
     
     
         17 . The method of  claim 14 , wherein the pulser of the plurality of pulsers is configured to provide a bipolar pulse to at least one ultrasonic transducer of the plurality of ultrasonic transducers. 
     
     
         18 . The method of  claim 14 , wherein the plurality of ultrasonic transducers comprise at least one capacitive ultrasonic transducer. 
     
     
         19 . The method of  claim 14 , wherein the input waveform is a first input waveform of a plurality of input waveforms and the pulser is a first pulser of the plurality of pulsers, and the method further comprises providing a second input waveform to a second pulser of the plurality of pulsers, wherein the first input waveform and the second input waveforms have different amplitudes. 
     
     
         20 . The method of  claim 14 , further comprising:
 generating a plurality of time-delayed versions of the input waveform;   providing the plurality of time-delayed versions of the input waveform to the plurality of pulsers.   
     
     
         21 . The method of  claim 14 , wherein providing the input waveform to the pulser of the plurality of pulsers coupled to the plurality of ultrasonic transducers comprises transmitting first and second data packets to the pulser serially.