Systems and methods for providing an auto-calibrated voltage reference

• US 10,401,886 B1
• Filed: 07/30/2015
• Issued: 09/03/2019
• Est. Priority Date: 07/30/2014
• Status: Active Grant

• Current Assignee: Cirrus Logic Incorporated
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Melanson, John L., Singh, Rahul, Drakshappalli, Prashanth, Brummel, Dale
• Primary Examiner(s): Ahmed, Yusef A
• Assistant Examiner(s): Singh, David A.
• Application Number:
  US14/813,549
• Time in Patent Office: 1,496 Days
• Field of Search: 323234, 323265, 323273, 323281
• CPC Class Codes: G05F 1/462 as a function of the requirements of the load, e.g. delay, temperature, specific voltage/current characteristic
• CPC Class Codes: G05F 1/468 characterised by reference voltage circuitry, e.g. soft start, remote shutdown
• CPC Class Codes: G05F 1/56 using semiconductor devices in series with the load as final control devices G05F1/461 takes precedence
• CPC Class Codes: G05F 1/565 sensing a condition of the system or its load in addition to means responsive to deviations in the output of the system, e.g. current, voltage, power factor G05F1/563 takes precedence

Abstract

A system may include a first voltage reference for generating a first voltage for operating a circuit, a second voltage reference having a higher precision than the first voltage reference, and a controller. The controller may be configured to determine a presence or an absence of a condition for calibrating the first voltage reference. The controller may also be configured to, responsive to the presence of the condition, enable the second voltage reference to generate a second voltage for calibrating the first voltage reference. The controller may further be configured to, responsive to the absence of the condition, disable the second voltage reference.

Claims

1. A controller configured to:

determine a presence or an absence of a condition for calibrating a first voltage reference for generating a first voltage for operating a circuit, wherein the condition includes an expiration of a timer indicative of a passage of time from a previous calibration of the first voltage reference, and wherein a time duration associated with the timer depends upon a rate of change of a temperature associated with the circuit;

responsive to the presence of the condition, enable a second voltage reference to generate a second voltage for calibrating and controlling the first voltage wherein the second voltage reference has a higher precision than the first voltage reference; and

responsive to the absence of the condition, disable the second voltage reference.

2. The controller of claim 1, wherein the circuit comprises an analog-to-digital converter.

3. The controller of claim 2, wherein the analog-to-digital converter is integral to an integrated circuit comprising the first voltage reference and the controller.

4. The controller of claim 2, wherein the analog-to-digital converter is integral to a data acquisition system.

5. The controller of claim 2, wherein the analog-to-digital converter is configured to sample data from a seismic sensor.

6. The controller of claim 1, wherein the first voltage reference and the second voltage reference are configured to receive electrical energy for operation from a battery.

7. A method comprising:

determining a presence or an absence of a condition for calibrating a first voltage reference, the first voltage reference for generating a first voltage for operating a circuit, wherein the condition includes an expiration of a timer indicative of a passage of time from a previous calibration of the first voltage reference, and wherein a time duration associated with the timer depends upon a rate of change of a temperature associated with the circuit;

responsive to the presence of the condition, enabling a second voltage reference to generate a second voltage for calibrating and controlling the first voltage, the second voltage reference having higher precision than the first voltage reference; and

responsive to the absence of the condition, disabling the second voltage reference.

8. The method of claim 7, wherein the circuit comprises an analog-to-digital converter.

9. The method of claim 8, wherein the analog-to-digital converter is integral to an integrated circuit comprising the first voltage reference and the controller.

10. The method of claim 8, wherein the analog-to-digital converter is integral to a data acquisition system.

11. The method of claim 8, wherein the analog-to-digital converter samples data from a seismic sensor.

12. The method of claim 7, wherein the first voltage reference and the second voltage reference receive electrical energy for operation from a battery.

13. A system comprising:

a first voltage reference for generating a first voltage for operating a circuit;

a second voltage reference having higher precision than the first voltage reference; and

a controller configured to;

determine a presence or an absence of a condition for calibrating the first voltage reference, wherein the condition includes an expiration of a timer indicative of a passage of time from a previous calibration of the first voltage reference, and wherein a time duration associated with the timer depends upon a rate of change of a temperature associated with the system;

responsive to the presence of the condition, enable the second voltage reference to generate a second voltage for calibrating and controlling the first voltage reference; and

responsive to the absence of the condition, disable the second voltage reference.