Predictive current sensing

Patent metadata

Field	Value
Publication number	US-9639102-B2
Application number	US-201313770982-A
Country	US
Kind code	B2
Filing date	Feb 19, 2013
Priority date	Feb 19, 2013
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

A system and method are provided for estimating current. A current source is configured to generate a current and a pulsed sense enable signal is generated. An estimate of the current is generated and the estimate of the current is updated based on a first signal that is configured to couple the current source to an electric power supply and a second signal that is configured to couple the current source to aloud. A system includes the current source and a current prediction unit. The current source is configured to generate a current. The current prediction unit is coupled the current source and is configured to generate the estimate of the current and update the estimate of the current based on the first signal and the second signal.

First claim

What is claimed is:

1. A method, comprising:
configuring a current source to generate a current;
initializing an estimate of the current;
summing the estimate of the current with a first parameter while a first signal couples the current source to an electric power supply;
maintaining the estimate of the current while the first signal decouples the current source from the electric power supply;
summing a second parameter with the estimate of the current while a second signal couples the current source to a load; and
summing a third parameter with the estimate of the current to update the estimate of the current while the second signal decouples the current source from the load.

2. The method of claim 1 , further comprising sampling a sense voltage across a resistive sense mechanism according to a pulsed sense enable signal, wherein the sense voltage represents a measurement of the current.

3. The method of claim 2 , further comprising generating a pulse of the pulsed sense enable signal when the estimate of the current exceeds a switching threshold value.

4. The method of claim 1 , further comprising adjusting an amount of the current that is generated by the current source based on a comparison between a reference current and the estimate of the current.

5. The method of claim 4 , wherein the reference current is set according to a processing workload.

6. The method of claim 1 , wherein the current is greater than an average current that is needed to regulate an output voltage level at the load.

7. The method of claim 1 , wherein the generating of the current comprises alternately enabling a first switching mechanism to couple the current source to the electric power source while disabling a second switching mechanism to decouple the current source from a current sink based on a periodic signal and then disabling the first switching mechanism to decouple the current source from the electric power source while enabling the second switching mechanism to couple the current source to the current sink based on the estimate of the current.

8. The method of claim 1 , wherein the generating of the current comprises alternately enabling a first switching mechanism to couple the current source to the electric power source while disabling a second switching mechanism to decouple the current source from a current sink based on a periodic signal and then disabling the first switching mechanism to decouple the current source from the electric power source while enabling the second switching mechanism to couple the current source to the current sink based on a measurement of the current.

9. The method of claim 1 , further comprising:
periodically measuring the current near a minimum level and near a maximum level; and
updating the estimate of the current based on the current measured at the minimum level and at the maximum level.

10. The method of claim 1 , wherein the first parameter increases the estimate of the current.

11. The method of claim 1 , wherein the second parameter and the third parameter decrease the estimate of the current.

12. The method of claim 1 , further comprising:
measuring a duty factor associated with the second signal; and
updating the estimate of the current based on the duty factor.

13. An electric power conversion device, comprising:
a current source that is configured to generate a current; and
a current prediction unit that is coupled to the current source and configured to:
initialize an estimate of the current;
sum the estimate of the current with a first parameter while a first signal couples the current source to an electric power supply;
maintain the estimate of the current while the first signal decouples the current source from the electric power supply;
sum a second parameter with the estimate of the current while a second signal couples the current source to a load; and
sum a third parameter with the estimate of the current to update the estimate of the current while the second signal decouples the current source from the load.

14. The electric power conversion device of claim 13 , wherein the current prediction unit is further configured to sample a sense voltage across a resistive sense mechanism according to a pulsed sense enable signal, wherein the sense voltage represents a measurement of the current.

15. The electric power conversion device of claim 14 , wherein the current prediction unit is further configured to generate the pulse of the pulsed sense enable signal when the estimate of the current exceeds a switching threshold value.

16. The electric power conversion device of claim 13 , wherein the current prediction unit is further configured to adjust an amount of the current that is generated by the current source based on a comparison between a reference current and the estimate of the current.

Assignees

• Nvidia Corp

Inventors

• Dally William J

Classifications

• H02M2001/0016

  Electricity · mapped topic

• H02M3/1588

  comprising at least one synchronous rectifier element (H02M3/1582, H02M3/1584 take precedence) · CPC title

• H02M2003/1586

  Electricity · mapped topic

• G05F1/563 Primary

  including two stages of regulation at least one of which is output level responsive, e.g. coarse and fine regulation · CPC title

• H02M2001/0032

  Electricity · mapped topic