Power management in a complex integrated circuit

1. An integrated circuit device comprising:

a plurality of processing cores;

a primary power grid coupled to at least one power source for distributing power to the plurality of processing cores;

a plurality of secondary power grids, wherein each secondary power grid is coupled to a respective one of the processing cores;

a plurality of sets of power gates, wherein each set of power gates is configured to provide one or more power paths between the primary power grid and a respective one of the secondary power grids to provide power to a corresponding processing core; and

a control circuit that, in response to one of the processing cores being turned on or off, switches the set of power gates allocated to that processing core in a sequence that provides a nonlinear rate of impedance change between the primary power grid and the secondary power grid corresponding to that processing core, wherein the nonlinear rate of impedance change is based on a monitoring result, the monitoring result being based on monitoring an electrical parameter of at least one of the processing cores of the integrated circuit during a previous core activation period.

2. The integrated circuit device of claim 1 , wherein each set of power gates comprises a plurality of power gate groups of different impedances.

3. The integrated circuit device of claim 1 , wherein the nonlinear rate of impedance change follows an exponential function.

4. The integrated circuit device of claim 1 , wherein the plurality of sets of power gates includes more than a hundred power gates, more than a thousand power gates, or more than ten thousand power gates.

5. An integrated circuit comprising:

a first set of conductors coupled to at least one power source;

a second set of conductors coupled to a first power consuming portion of an integrated circuit;

multiple power gates coupled between the first and second sets of conductors; and

a control circuit configured to activate the multiple power gates during an activation period to provide a nonlinear rate of change of an impedance between the first and the second sets of conductors during the activation period, wherein the nonlinear rate of change is based on a monitoring result, the monitoring result being based on monitoring an electrical parameter of at least one of the first power consuming portion or a second power consuming portion of the integrated circuit during a previous core activation period.

6. The integrated circuit according to claim 5 , wherein the control circuit is configured to increase a number of active power gates during the activation period in a nonlinear manner.

7. The integrated circuit according to claim 5 , wherein the control circuit is configured to vary a number of active power gates during the activation period in a nonlinear manner.

8. The integrated circuit according to claim 5 , wherein change of the impedance follows an exponential function.

9. The integrated circuit according to claim 5 , wherein the at least one power source comprises a main power source, a first secondary power source, and a second secondary power source; wherein the second secondary power source is configured to provide power to a second power consuming portion of the integrated circuit.

10. The integrated circuit according to claim 9 , wherein the nonlinear rate of change of the impedance reduces a current being drawn by the first power consuming portion from the second secondary power source during the activation period.

11. The integrated circuit according to claim 5 , wherein the multiple power gates are arranged in groups of power gates that are independently controlled from each other.

12. The integrated circuit according to claim 5 , wherein the multiple power gates are arranged in groups of power gates that form a daisy chain.

13. A method for managing power in an integrated circuit, the method comprising:

receiving, by a control circuit, a signal to activate a first power consuming portion of the integrated circuit, the integrated circuit comprising a first set of conductors coupled to at least one power source, the integrated circuit further comprising a second set of conductors coupled to the first power consuming portion, multiple power gates being coupled between the first and second sets of conductors; and

activating, by the control circuit, the multiple power gates during a core activation period to provide a nonlinear rate of change of an impedance between the first and second sets of conductors during the core activation period, wherein the nonlinear rate of change is based on a monitoring result, the monitoring result being based on monitoring an electrical parameter of at least one of the first power consuming portion or a second power consuming portion of the integrated circuit during a previous core activation period.

14. The method according to claim 13 , wherein activating the multiple power gates during the core activation period comprises increasing a number of active power gates during the core activation period in a nonlinear manner.

15. The method according to claim 13 , wherein activating the multiple power gates during the core activation period comprises varying a number of active power gates during the core activation period in a nonlinear manner.

16. The method according to claim 13 , wherein the change of the impedance follows an exponential function.

17. The method according to claim 13 , wherein the at least one power source comprises a main power source, a first secondary power source, and a second secondary power source; wherein the method further comprises providing by the second secondary power source power to a second power consuming portion of the integrated circuit.

18. The method according to claim 13 , wherein the multiple power gates are configured in groups of power gates that are independently controlled from each other.

19. The method according to claim 13 , wherein the multiple power gates are configured in groups of power gates that form a daisy chain.