Controlling current in a switching regulator

1. An electronically-implemented method of current limiting, the method comprising:

sampling a signal associated with an inductor current of a switching regulator to generate a sampled level, wherein timing of sampling is performed relative to one of switching on or off of a transistor configured to pass current through an inductor to a load, and wherein said sampling is performed while current flowing through the inductor is increasing;

adjusting a current limit threshold based at least partly on a comparison between the sampled level and a reference level;

comparing the signal to the current limit threshold using a current limiting comparator;

generating a control signal based on a node in a signal path between the current limiting comparator and a control terminal of the transistor, wherein there is at least one intervening circuit element between the current limiting comparator and the node in the signal path, and wherein said sampling occurs when the control signal is asserted; and

limiting an output current of the switching regulator based at least partly on said comparing.

2. The method of claim 1 , further comprising disabling at least a portion of a current adjustment circuit configured to perform said adjusting, in response to detecting that the output current of the switching regulator is not being limited based on the current limit threshold.

3. The method of claim 1 , wherein said adjusting and said limiting cause the switching regulator to operate in a dynamic stable state to limit the output current of the switching regulator.

4. The method of claim 1 , further comprising latching data indicative of a result of the comparison between the sampled level and the reference level in a clock cycle after said adjusting.

5. The method of claim 1 , wherein the at least one intervening circuit element comprises at least one of a level shifter or a driver.

6. The method of claim 1 , wherein the sampled level is stored via a capacitive circuit element.

7. The method of claim 1 , wherein the transistor is electrically connected to Vdd.

8. A switching regulator comprising:

a current limiting comparator configured to perform a comparison of a current limit threshold with an indication of current passing through an output circuit element of the switching regulator, wherein the current limiting comparator is configured to cause the current passing through the output circuit element of the switching regulator to be limited based on the comparison;

a compare circuit configured to compare a reference current with a stored indication of current flowing through the output circuit element;

a current adjustment circuit configured to adjust the current limit threshold based on an output of the compare circuit; and

a storage element configured to store the indication of the current flowing through the output circuit element when current flow through the output circuit element is increasing and when a control signal is asserted wherein the control signal is generated based on a node in a signal path between the current limiting comparator and the output circuit element, and wherein at least one intervening circuit element is between the current limiting comparator and the node in the signal path.

9. The switching regulator of claim 8 , wherein the switching regulator comprises a buck converter.

10. The switching regulator of claim 8 , further comprising a switch configured to selectively enable the storage element to store the indication of current passing through the output circuit element based on the control signal.

11. The switching regulator of claim 10 , further comprising a level shifter and a driver in the signal path, wherein the at least one intervening circuit element comprises the level shifter and the driver.

12. The switching regulator of claim 11 , further comprising a second level shifter disposed in an electrical path between the node and the switch.

13. The switching regulator of claim 8 , wherein the current adjustment circuit comprises at least one of a counter or an analog-to-digital converter.

14. The switching regulator of claim 8 , further comprising:

a state element configured to latch an output of the current limiting comparator;

a level shifter configured to increase a voltage level of an output of the state element, wherein the at least one intervening circuit element comprises the state element and the level shifter; and

one or more drivers configured to receive an input from the level shifter and control activation of the transistor that is configured to cause current to pass through the output circuit element.

15. The switching regulator of claim 8 , wherein the current adjustment circuit is configured to generate an output with a dynamic stable state to cause current passing through the output circuit element to be limited.

16. The switching regulator of claim 8 , wherein the output circuit element comprises an inductor.

17. The switching regulator of claim 8 , further comprising a level shifter in the signal path, wherein the at least one intervening circuit element comprises the level shifter.

18. The switching regulator of claim 8 , further comprising a level shifter and a driver in the signal path, wherein the at least one intervening circuit element comprises the level shifter and the driver.

19. A switching regulator comprising:

a current limiting comparator configured to perform a comparison of a current limit threshold with an indication of current passing through an output circuit element of the switching regulator, wherein the current limiting comparator is configured to cause the current passing through the output circuit element of the switching regulator to be limited based on the comparison;

a compare circuit configured to compare a reference current with a stored indication of current flowing through the output circuit element;

a current adjustment circuit configured to adjust the current limit threshold based on an output of the compare circuit, wherein the current adjustment circuit is configured to be disabled in response to the current limiting comparator generating an output signal indicative of the current limit threshold being greater than the indication of current flowing through the output circuit element; and

a storage element configured to store the indication of the current flowing through the output circuit element when a control signal is asserted, wherein the control signal is generated based on a node in a signal path between the current limiting comparator and the output circuit element, and wherein at least one intervening circuit element is between the current limiting comparator and the node in the signal path.