# US 2018/0321365 A1 · Symmetric receiver switch for bipolar pulser > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0321365 A1 - Document ID: US20180321365A1 - Status: Published application - Kind: A1 - Application number: 16/035,552 - Filed: 2018-07-13 - Published: 2018-11-08 - Earliest claimed: 2016-03-31 - Assignees: Butterfly Network, Inc. - Applicants: Butterfly Network, Inc. - Inventors: Kailiang Chen; Tyler S. Ralston; Keith G. Fife - Web page: https://patentgrep.com/patent/US20180321365A1 ## CPC - G01S 7/521: Constructional features - G01S 7/52017: {particularly adapted to short-range imaging (G01S7/53 takes precedence)} - G01S 7/5202: {for pulse systems} - G01S 7/52047: {for elimination of side lobes or of grating lobes; for increasing resolving power} - G01S 7/5205: {Means for monitoring or calibrating} - G01S 7/5208: {with integration of processing functions inside probe or scanhead} - G01S 15/8915: {using a transducer array} - H03K 17/6874: {in a symmetrical configuration} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) ## Abstract Circuitry for ultrasound devices is described. A multilevel pulser is described, which can provide bipolar pulses of multiple levels. The multilevel pulser includes a pulsing circuit and pulser and feedback circuit. Symmetric switches are also described. The symmetric switches can be positioned as inputs to ultrasound receiving circuitry to block signals from the receiving circuitry. ## Claims ### Claim 1 A method of operating an ultrasound device, comprising: providing a pulser signal to an ultrasonic transducer during a transmit mode of operation of the ultrasound device; operating a symmetric switch having an input terminal coupled between the ultrasonic transducer and a receiving circuit in an open state during the transmit mode of operation; operating the symmetric switch in a closed state during a receive mode of operation of the ultrasound device; and converting, using a current-to-voltage converter of the receiving circuit, a current from the ultrasonic transducer to a voltage during the receive mode of operation. ### Claim 2 (depends on 1) The method of claim 1, wherein the current-to-voltage converter comprises a trans-impedance amplifier (TIA), and converting the current from the ultrasonic transducer to the voltage during the receive mode of operation is performed using the TIA. ### Claim 3 (depends on 1) The method of claim 1, wherein the symmetric switch comprises a first transistor and a second transistor, the first transistor having a first gate, a first source, and a first drain, and the second transistor having a second gate, a second source, and a second drain, the first gate being connected to the second gate, and the first source being connected to the second source, and wherein operating the symmetric switch in the open state during the transmit mode of operation of the ultrasound device comprises coupling the first gate, the second gate, the first source, and the second source to a same electric potential. ### Claim 4 (depends on 1) The method of claim 1, further comprising operating a third transistor during the receive mode and the transmit mode. ### Claim 5 (depends on 4) The method of claim 4, wherein the third transistor has a third gate, a third drain connected to the second drain, and a third source, and wherein operating the third transistor comprises: during the receive mode, coupling the third gate to a first electric potential; and during the transmit mode, coupling the third gate to a second electric potential that is greater than the first electric potential. ### Claim 6 (depends on 4) The method of claim 4, wherein the third transistor has a third gate, a third drain connected to the second drain, and a third source, and wherein the method further comprises coupling the third source to a ground potential. ### Claim 7 (depends on 1) The method of claim 1, wherein the symmetric switch comprises a first transistor and a second transistor, the first transistor having a first gate, a first source, and a first drain, and the second transistor having a second gate, a second source, and a second drain, the first gate being connected to the second gate, and the first drain being connected to the second drain, and wherein operating the symmetric switch in the open state during the transmit mode of operation of the ultrasound device comprises coupling the first gate, the second gate, the first drain, and the second drain to a same electric potential. ### Claim 8 (depends on 7) The method of claim 7, further comprising operating a third transistor during the receive mode and the transmit mode. ### Claim 9 (depends on 8) The method of claim 8, wherein the third transistor has a third gate, a third drain connected to the second source, and a third source, and wherein operating the third transistor comprises: during the receive mode, coupling the third gate to a first electric potential; and during the transmit mode, coupling the third gate to a second electric potential that is greater than the first electric potential. ### Claim 10 (depends on 8) The method of claim 8, wherein the third transistor has a third gate, a third drain connected to the second source, and a third source, the method further comprising coupling the third source to a ground potential.