APPARATUS AND METHODS FOR EXTENDING SENSOR INTEGRATED CIRCUIT OPERATION THROUGH A POWER DISTURBANCE

• US 20170117801A1
• Filed: 09/19/2016
• Published: 04/27/2017
• Est. Priority Date: 10/21/2015
• Status: Active Grant

• Current Assignee: Allegro Microsystems Incorporated (Sanken Electric Company Limited)
• Original Assignee: Allegro Microsystems Incorporated (Sanken Electric Company Limited)
• Inventors: Shoemaker, Eric G., Scheller, P. Karl, Fernandez, Devon
• Granted Patent: US 10,411,498 B2
• Time in Patent Office: Days
• CPC Class Codes: G01D 11/00 Component parts of measuring arrangements not specially adapted for a specific variable G01D13/00, G01D15/00 take precedence
• CPC Class Codes: H01L 23/49589 Capacitor integral with or on the leadframe
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices

Abstract

A sensor integrated circuit includes an energy storage device having a first terminal coupled to a functional circuit and a blocking circuit coupled between a power supply pin and the first terminal of the energy storage device. The blocking circuit permits the energy storage device to store energy from an external power supply coupled to the power pin. The first terminal of the energy storage device is inaccessible from outside of the sensor IC. Additional features of the sensor IC can include a high regulator, a low regulator, and a low power circuit.

Claims

1. A sensor integrated circuit having a power pin for coupling to an external power supply, a reference pin, and a functional circuit, comprising:

an energy storage device having a first terminal coupled to the functional circuit; and

a blocking circuit coupled between the power pin and the first terminal of the energy storage device and configured to permit the energy storage device to store energy from the external power supply, wherein the first terminal of the energy storage device is inaccessible from outside of the sensor integrated circuit.

2. The sensor integrated circuit of claim 1 wherein the energy storage device comprises a capacitor having a second terminal coupled to the reference pin.

3. The sensor integrated circuit of claim 2 further comprising a first regulator coupled between the blocking circuit and the first terminal of the capacitor.

4. The sensor integrated circuit of claim 3 wherein the first regulator has an input coupled to the power pin and provides a voltage to the capacitor that is higher than a voltage of the external power supply.

5. The sensor integrated circuit of claim 4 wherein the first regulator comprises a Boost regulator or a charge pump.

6. The sensor integrated circuit of claim 2 further comprising a first regulator having an input coupled to the power pin, an output coupled to the first terminal of the capacitor, wherein the first regulator comprises the blocking circuit.

7. The sensor integrated circuit of claim 6 wherein the first regulator has an input coupled to the power pin and provides a voltage to the capacitor that is higher than a voltage of the external power supply.

8. The sensor integrated circuit of claim 7 wherein the first regulator comprises a Boost regulator or a charge pump.

9. The sensor integrated circuit of claim 1 further comprising a second regulator coupled between the first terminal of the energy storage device and the functional circuit.

10. The sensor integrated circuit of claim 9 wherein the second regulator comprises a linear regulator.

11. The sensor integrated circuit of claim 1 wherein the blocking circuit comprises a uni-directional switch.

12. The sensor integrated circuit of claim 11 wherein the blocking circuit comprises one or more of a diode, a diode-connected transistor, or an active switch.

13. The sensor integrated circuit of claim 1 further comprising a low power circuit responsive to a voltage across the energy storage device, a voltage across the power and reference pins, or both to cause the functional circuit to enter a low power mode of operation.

14. A sensor integrated circuit having a power pin for coupling to an external power supply, a reference pin, and a functional circuit, comprising:

an energy storage device having a first terminal coupled to the functional circuit; and

a first regulator having an input coupled to the power pin and an output coupled to the first terminal of the energy storage device, wherein the first regulator provides a voltage higher than a voltage of the external power supply to the capacitor.

15. The sensor integrated circuit of claim 14 further comprising a blocking circuit coupled between the power pin and the first terminal of the energy storage device and configured to permit the energy storage device to store energy from the external power supply.

16. The sensor integrated circuit of claim 15 wherein the blocking circuit comprises a uni-directional switch.

17. The sensor integrated circuit of claim 16 wherein the blocking circuit comprises one or more of a diode, a diode-connected transistor, or an active switch.

18. The sensor integrated circuit of claim 14 wherein the first regulator comprises a blocking circuit configured to permit the energy storage device to store energy from the external power supply.

19. The sensor integrated circuit of claim 18 wherein the blocking circuit comprises a uni-directional switch.

20. The sensor integrated circuit of claim 19 wherein the blocking circuit comprises one or more of a diode, a diode-connected transistor, or an active switch.

21. The sensor integrated circuit of claim 14 wherein the first regulator comprises a Boost regulator or a charge pump.

22. The sensor integrated circuit of claim 14 further comprising a second regulator coupled between the first terminal of the energy storage device and the functional circuit.

23. The sensor integrated circuit of claim 18 wherein the second regulator comprises a linear regulator.

24. The sensor integrated circuit of claim 14 further comprising a low power circuit responsive to a voltage across the energy storage device, a voltage across the power and reference pins, or both to cause the functional circuit to enter a low power mode of operation.

25. The sensor integrated circuit of claim 14 wherein the first terminal of the energy storage device is inaccessible from outside of the integrated circuit.

26. The sensor integrated circuit of claim 14 wherein the energy storage device comprises one or more of a capacitor or an inductor.

27. A sensor integrated circuit having a power pin for coupling to an external power supply, a reference pin, and a functional circuit, comprising:

a capacitor having a first terminal coupled to the functional circuit is inaccessible from outside of the integrated circuit and further comprising a second terminal coupled to the reference pin;

a blocking circuit coupled between the power pin and the first terminal of the capacitor and configured to permit the capacitor to store energy from the external power supply;

a first regulator coupled between the blocking circuit and the first terminal of the capacitor;

a second regulator coupled between the first terminal of the capacitor and the functional circuit; and

a low power circuit responsive to a voltage across the capacitor, a voltage across the power and reference pins, or both to cause the functional circuit to enter a low power mode of operation.

28. The sensor integrated circuit of claim 27 wherein the first regulator provides a voltage to the capacitor that is higher than a voltage of the external power supply.

29. The sensor integrated circuit of claim 28 wherein the first regulator comprises a Boost regulator or a charge pump.

30. The sensor integrated circuit of claim 27 wherein the second regulator comprises a linear regulator.

31. The sensor integrated circuit of claim 27 wherein the blocking circuit comprises a uni-directional switch.

32. The sensor integrated circuit of claim 31 wherein the blocking circuit comprises one or more of a diode, a diode-connected transistor, or an active switch.

33. A sensor integrated circuit comprising:

a lead frame comprising at least two externally accessible leads configured to permit external power and ground connections to the sensor integrated circuit; and

a capacitor having a first terminal and a second terminal, wherein the first terminal of the capacitor is isolated from the externally accessible leads and the second terminal is coupled to at least one of the externally accessible leads.

34. The sensor integrated circuit of claim 33 wherein the lead frame comprises an externally inaccessible lead coupled to the first terminal of the capacitor.

35. The sensor integrated circuit of claim 34 wherein each of the at least two externally accessible leads and the externally inaccessible lead has a respective die attach portion to which a semiconductor die is attached.

36. The sensor integrated circuit of claim 33 further comprising a non-conductive mold material enclosing the capacitor and the semiconductor die.

37. The sensor integrated circuit of claim 33 further comprising a second capacitor having a first terminal and a second terminal coupled between the at least two externally accessible leads.