Symmetric receiver switch for bipolar pulser
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.
1. An apparatus, comprising:
a metal oxide semiconductor (MOS) die having ultrasonic transducers and an integrated circuitry formed thereon, the integrated circuit including an array of symmetric switches coupled to an array of ultrasonic transducers,
wherein a first symmetric receiver switch of the array of symmetric receiver switches comprises a first transistor and a second transistor, the first symmetric receiver switch having an input terminal coupled between the output terminal of a bipolar pulser and an ultrasonic transducer;
wherein the first transistor has a first gate, a first source and a first drain and the second transistor has a second gate, a second source and a second drain, and wherein the first gate is connected to the second gate and the first source is connected to the second source, and wherein the first gate and the first source are coupled or couplable to a first same electric potential at a first time, and to a second same electric potential at a second time.
2. An ultrasound device, comprising:
an ultrasonic transducer;
a receiving circuit configured to process an electrical signal output by the ultrasonic transducer, wherein the receiving circuit comprises a current-to-voltage converter; and
a symmetric switch having an input terminal coupled between the ultrasonic transducer and the receiving circuit.
3. The ultrasound device of claim 2 , wherein the current-to-voltage converter comprises a trans-impedance amplifier (TIA).
4. The ultrasound device of claim 2 , 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 is connected to the second gate; and
the first source is connected to the second source.
5. The ultrasound device of claim 4 , wherein the first gate, the second gate, the first source, and the second source are coupled or couplable to a same electric potential.
6. The ultrasound device of claim 4 , further comprising a third transistor having a third drain connected to the second drain.
7. The ultrasound device of claim 6 , wherein the third transistor has a third source connected to a ground potential.
8. The ultrasound device of claim 2 , 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 is connected to the second gate; and
the first drain is connected to the second drain.
9. The ultrasound device of claim 8 , wherein the first gate, the second gate, the first drain, and the second drain are coupled or couplable to a same electric potential.
10. The ultrasound device of claim 8 , further comprising a third transistor having a third drain connected to the second source.
11. The ultrasound device of claim 10 , wherein the third transistor has a third source connected to a ground potential.