Trans-impedance amplifier for ultrasound device and related apparatus and methods

Patent metadata

Field	Value
Publication number	US-11863133-B2
Application number	US-202117331538-A
Country	US
Kind code	B2
Filing date	May 26, 2021
Priority date	Dec 2, 2015
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

A variable current trans-impedance amplifier (TIA) for an ultrasound device is described. The TIA may be coupled to an ultrasonic transducer to amplify an output signal of the ultrasonic transducer representing an ultrasound signal received by the ultrasonic transducer. During acquisition of the ultrasound signal by the ultrasonic transducer, one or more current sources in the TIA may be varied.

First claim

What is claimed is:

1. An ultrasound apparatus, comprising:
an ultrasound sensor;
a variable current trans-impedance amplifier (TIA) coupled to the ultrasound sensor and configured to receive and amplify an output signal from the ultrasound sensor, the variable current TIA being a multi-stage operational amplifier having a first stage and a last stage;
wherein the variable current TIA further comprises a variable impedance circuit coupled between an output terminal of the variable current TIA and a node representing an input to the last stage; and
wherein the variable current TIA further comprises a variable feedback impedance circuit coupled between the output terminal of the variable current TIA and a node representing an input to the first stage.

2. The ultrasound apparatus of claim 1 , wherein the variable current TIA includes a first variable current source coupled to the first stage and a second variable current source coupled to the last stage.

3. The ultrasound apparatus of claim 2 , wherein the first and second variable current sources are independently controllable.

4. The ultrasound apparatus of claim 2 , wherein the first and second variable current sources are digitally programmable.

5. The ultrasound apparatus of claim 2 , further comprising a control circuit coupled to the first variable current source and the second variable current source and configured to control a first amount of current through the first variable current source and a second amount of current through the second variable current source.

6. The ultrasound apparatus of claim 5 , wherein the control circuit is configured, when controlling the first amount of current through the first variable current source and the second amount of current through the second variable current source, to increase the first amount of current through the first variable current source in intervals during an acquisition period and to decrease the second amount of current through the second variable current source in intervals during the acquisition period.

7. The ultrasound apparatus of claim 5 , wherein the control circuit is configured, when controlling the first amount of current through the first variable current source and the second amount of current through the second variable current source, to simultaneously increase the first amount of current through the first variable current source and decrease the second amount of current through the second variable current source after a time interval.

8. The ultrasound apparatus of claim 2 , wherein the first variable current source provides eight states for a current of the first variable current source.

9. The ultrasound apparatus of claim 2 , wherein the first variable current source comprises a first current source providing a first current, a second current source providing a second current, and a third current source providing a third current, the first current being approximately half of the second current and approximately a quarter of the third current.

10. The ultrasound apparatus of claim 1 , wherein the ultrasound sensor and the variable current TIA are monolithically integrated on a semiconductor chip.

11. The ultrasound apparatus of claim 1 , wherein the variable current TIA is configured, when amplifying the output signal, to decrease a noise floor of the variable current TIA during an acquisition period.

12. The ultrasound apparatus of claim 1 , wherein the first variable impedance circuit comprises a first series of circuit components connected in parallel to a second series of circuit components, wherein:
the first series of circuit components comprises:
a first switch, a first capacitor, and a first resistor connected in series; or
a first switch connected in series with a parallel connection of a first capacitor and a first resistor; and

the second series of circuit components comprises:
a second switch, a second capacitor, and a second resistor connected in series; or
a second switch connected in series with a parallel connection of a second capacitor and a second resistor.

13. The ultrasound apparatus of claim 1 , further comprising a control circuit configured to vary a feedback impedance of the variable impedance circuit based on a gain setting of the variable current TIA.

14. The ultrasound apparatus of claim 13 , wherein the control circuit is further configured to vary a current of the variable current TIA in concert with varying the feedback impedance of the variable impedance circuit.

15. A method, comprising:
acquiring an ultrasound signal with an ultrasound sensor during an acquisition period and outputting, from the ultrasound sensor, an analog electrical signal representing the ultrasound signal; and
amplifying the analog electrical signal with a variable current trans-impedance amplifier (TIA) having a first stage, a last stage, a variable impedance circuit coupled between an output terminal of the variable current TIA and a node representing an input to the last stage, and a variable feedback impedance circuit coupled between the output terminal of the variable current TIA and a node representing an input to the first stage, wherein amplifying the analog electrical signal comprises varying a feedback impedance of the variable impedance circuit during the acquisition period.

16. The method of claim 15 , wherein amplifying the analog electrical signal with the variable current TIA further comprises varying a current of the variable current TIA during the acquisition period.

17. The method of claim 16 , wherein varying the feedback impedance of the variable impedance circuit further comprises varying the feedback impedance in concert with varying the current.

18. The method of claim 15 , wherein varying the feedback impedance of the first variable impedance circuit during the acquisition period comprises varying the feedback impedance of the variable impedance circuit based on a gain setting of the variable current TIA.

19. The method of claim 15 , wherein the variable impedance circuit comprises a first series of circuit components connected in parallel to a second series of circuit components, wherein:
the first series of circuit components comprises:
a first switch, a first capacitor, and a first resistor connected in series; or
a first switch connected in series with a parallel connection of a first capacitor and a first resistor; and

the second series of circuit components comprises:
a second switch, a second capacitor, and a second resistor connected in series; or
a second switch connected in series with a parallel connection of a second capacitor and a second resistor.

20. An ultrasound apparatus, comprising:
an ultrasound sensor; and
a variable current trans-impedance amplifier (TIA) coupled to the ultrasound sensor and configured to receive and amplify an output signal from the ultrasound sensor, the variable current TIA being a multi-stage operational amplifier having:
a first stage;
a last stage;
a first variable current source coupled to the first stage; and
a second variable current source coupled to the last stage; and
a control circuit coupled to the first variable current source and the second variable current source and configured to simultaneously increase a first amount of current through the first variable current source and decrease a second amount of current through the second variable current source after a time interval.

Assignees

• Bfly Operations Inc

Inventors

• Chen Kailiang
• Fife Keith G
• Sanchez Nevada J
• Casper Andrew J
• Ralston Tyler S

Classifications

• H03F3/16 Primary

  with field-effect devices · CPC title

• A61B5/6801

  specially adapted to be attached to or worn on the body surface · CPC title

• A61B8/4444

  related to the probe · CPC title

• G01S7/52025

  for pulse systems (G01S7/52034 takes precedence) · CPC title

• H03F1/086 Primary

  with FET's · CPC title