METHODS AND CIRCUITRY FOR BUILT-IN SELF-TESTING OF CIRCUITRY AND/OR TRANSDUCERS IN ULTRASOUND DEVICES
Aspects of the technology described herein relate to built-in self-testing (BIST) of circuitry (e.g., a pulser or receive circuitry) and/or transducers in an ultrasound device. A BIST circuit may include a transconductance amplifier coupled between a pulser and receive circuitry, a capacitor network coupled between a pulser and receive circuitry, and/or a current source couplable to the input terminal of receive circuitry to which a transducer is also couplable. The collapse voltages of transducers may be characterized using BIST circuitry, and a bias voltage may be applied to the membranes of the transducers based at least in part on their collapse voltages. The capacitances of transducers may also be measured using BIST circuitry and a notification may be generated based on the sets of measurements.
1 . An ultrasound device, comprising:
a pulser;
receive circuitry;
a capacitive micromachined ultrasonic transducer (CMUT) couplable to the receive circuitry; and
a transconductance amplifier coupled between the pulser and the receive circuitry.
2 . The ultrasound device of claim 1 , wherein the transconductance amplifier comprises a linearized transconductance amplifier.
3 . The ultrasound device of claim 1 , wherein the transconductance amplifier comprises a source-degenerated linearized transconductance amplifier.
4 . The ultrasound device of claim 1 , further comprising a resistor ladder, and wherein the transconductance amplifier and the pulser are configured to receive, as input signals, voltages from the resistor ladder.
5 . The ultrasound device of claim 1 , wherein the transconductance amplifier is coupled between the pulser and a circuit in the receive circuitry configurable as a transimpedance amplifier.
6 . The ultrasound device of claim 1 , wherein the transconductance amplifier is coupled between the pulser and a circuit in the receive circuitry configurable as a comparator.
7 . The ultrasound device of claim 1 , wherein the transconductance amplifier is coupled between the pulser and a circuit in the receive circuitry configurable as a delta-sigma analog-to-digital converter.
8 . The ultrasound device of claim 1 , wherein:
the pulser is configured to use a first power supply;
the transconductance amplifier is configured to use a second power supply;
the receive circuitry is configured to use a third power supply; and
the first power supply has a higher voltage than the second power supply and the second power supply has a higher voltage than the third power supply.
9 . The ultrasound device of claim 1 , wherein the transconductance amplifier can be turned off while the pulser and the receive circuitry remain on.
10 . The ultrasound device of claim 1 , wherein the pulser, the receive circuitry, the CMUT, and the transconductance amplifier are disposed within a single package.
11 . The ultrasound device of claim 1 , wherein the transconductance amplifier is disposed on a same semiconductor chip as the pulser, the receive circuitry, and/or the CMUT.
12 . The ultrasound device of claim 1 , wherein the transconductance amplifier comprises a built-in self-test (BIST) circuit.
13 . An ultrasound device, comprising:
receive circuitry having an input terminal;
a capacitive micromachined ultrasonic transducer (CMUT) couplable to the input terminal of the receive circuitry; and
a current source couplable to the input terminal of the receive circuitry.
14 . The ultrasound device of claim 13 , wherein:
the current source comprises a first current source configured to supply current to the input terminal of the receive circuitry; and
the ultrasound device further comprises a second current source couplable to the input terminal of the receive circuitry and configured to sink current from the input terminal of the receive circuitry.
15 . The ultrasound device of claim 13 , wherein the receive circuitry is capable of being configured as a comparator.
16 . The ultrasound device of claim 13 , wherein the pulser, the receive circuitry, the CMUT, and the current source are disposed within a single package.
17 . The ultrasound device of claim 13 , wherein the current source is disposed on a same semiconductor chip as the pulser, the receive circuitry, and/or the CMUT.
18 . The ultrasound device of claim 13 , wherein the current source comprises a built-in self-test (BIST) circuit.
19 . An ultrasound device, comprising:
receive circuitry having an input terminal;
a capacitor coupled to the input terminal of the receive circuitry; and
a current source couplable to the input terminal of the receive circuitry.
20 . The ultrasound device of claim 19 , wherein:
the current source comprises a first current source configured to supply current to the capacitor and thereby generate a first ramp voltage at the input terminal of the receive circuitry; and
the ultrasound device further comprises a second current source couplable to the input terminal of the receive circuitry and configured to sink current from the capacitor and thereby generate a second ramp voltage at the input terminal of the receive circuitry.
21 . The ultrasound device of claim 19 , wherein the receive circuitry is capable of being configured as a unity-gain amplifier.
22 . The ultrasound device of claim 19 , wherein the receive circuitry, the capacitor, and the current source are disposed within a single package.
23 . The ultrasound device of claim 19 , wherein the current source and the capacitor are disposed on a same semiconductor chip as the receive circuitry.
24 . The ultrasound device of claim 19 , wherein the current source and the capacitor comprise a built-in self-test (BIST) circuit.