Dynamic voltage transitions
The operating voltage of an integrated circuit (e.g., a processor) is changed in response to one or more conditions (e.g., a laptop computer is connected to an AC power source). Both the operating frequency and the operating voltage of the integrated circuit are changed. The voltage regulator providing the operating voltage to the integrated circuit is caused to transition between voltage levels using one or more intermediate steps. The integrated circuit continues to operate in the normal manner both at the new voltage and throughout the voltage transition.
1. A method comprising:
storing voltage step information for each supply voltage level for a plurality of supply voltage levels in separate memory locations in a memory, wherein the memory locations for the respective voltage step information of each supply voltage level storing
a respective first step voltage for a step increase in voltage from the respective each supply voltage level, and
a respective second step voltage for a step decrease in voltage from the respective each supply voltage level;
operating an integrated circuit at a first supply voltage level in the plurality of supply voltage levels;
determining a second supply voltage level to be provided to the integrated circuit based on the respective step voltage information of the first supply voltage level;
transmitting, from the integrated circuit to a voltage regulator, an indication of the determined second supply voltage level to be provided to the integrated circuit;
receiving the second supply voltage level from the voltage regulator; and
operating the integrated circuit at the second supply voltage level.
2. The method of claim 1 , wherein one of the first step voltage and the second step voltage of the first supply voltage level represents a size of a voltage transition from the first supply voltage level.
3. The method of claim 1 , wherein the memory locations for the respective voltage step information of each supply voltage level further storing voltage step time information indicating a time of a transition from the each supply voltage level.
4. The method of claim 3 , wherein indicating the time of the transition from the each supply voltage level includes indicating a required minimum time duration of operating at the each supply voltage level before an indication of a supply voltage level other than the each supply voltage level can be transmitted.
5. The method of claim 1 , wherein the second supply voltage level is in the plurality of supply voltage levels, the method further comprising:
transmitting, from the integrated circuit to the voltage regulator, an indication of a third supply voltage level to be provided to the integrated circuit, the transmitting based on the voltage step information stored in the respective memory location for the second supply voltage level;
receiving the third supply voltage level from the voltage regulator; and
operating the integrated circuit at the third supply voltage level.
6. A method comprising:
providing, with a voltage regulator, a first supply voltage level to an integrated circuit;
storing voltage step information for each supply voltage level for a plurality of supply voltage levels in separate memory locations in a memory, wherein the memory locations for the respective voltage step information of each supply voltage level storing
a respective first step voltage for a step increase in voltage from the respective each supply voltage level, and
a respective second step voltage for a step decrease in voltage from the respective each supply voltage level;
determining a second supply voltage level to be provided to the integrated circuit based on the respective step voltage information of the first supply voltage level;
receiving at the voltage regulator voltage step information indicating the determined second supply voltage level to be provided to the integrated circuit by the voltage regulator;
providing the second supply voltage level to the integrated circuit with the voltage regulator.
7. The method of claim 6 , wherein one of the first step voltage and the second step voltage of the first supply voltage level represents a size of a voltage transition from the first supply voltage level.
8. The method of claim 6 , wherein the memory locations for the respective voltage step information of each supply voltage level further storing voltage step time information indicating a time of a transition from the each supply voltage level.
9. The method of claim 8 , wherein indicating the time of the transition from the each supply voltage level includes indicating a required minimum time duration of operating at the each supply voltage level before an indication of a supply voltage level other than the each supply voltage level can be transmitted.
10. The method of claim 6 , wherein the second supply voltage level is in the plurality of supply voltage levels, the method further comprising:
receiving at the voltage regulator an indication of a third supply voltage level to be provided to the integrated circuit by the voltage regulator, the received indication based on the voltage step information stored in the respective memory location for the second supply voltage level;
providing the third supply voltage level to the integrated circuit with the voltage regulator.
11. An apparatus comprising:
a memory to store voltage step information for each supply voltage level for a plurality of supply voltage levels in separate memory locations in the memory, wherein the memory locations for the respective voltage step information of each supply voltage level storing
a respective first step voltage for a step increase in voltage from the respective each supply voltage level, and
a respective second step voltage for a step decrease in voltage from the respective each supply voltage level;
an integrated circuit having a control circuit and a voltage regulator controller coupled to the control circuit and to the memory, the voltage regulator controller to determine a second supply voltage level to be provided to the integrated circuit based on the respective step voltage information of a first supply voltage level of the plurality of supply voltage levels;
a voltage regulator coupled to the voltage regulator controller, wherein the voltage regulator provides the first supply voltage level to the integrated circuit and further wherein the voltage regulator controller transmits to the voltage regulator an indication of the determined second supply voltage level to be provided to the integrated circuit, and further wherein the voltage regulator provides the second supply voltage level to the integrated circuit in response to receiving the indication.
12. The apparatus of claim 11 , wherein one of the first step voltage and the second step voltage of the first supply voltage level represents a size of a voltage transition from the first supply voltage level.
13. The apparatus of claim 11 , wherein the memory locations for the respective voltage step information of each supply voltage level further storing voltage step time information indicating a time of a transition from the each supply voltage level.
14. The apparatus of claim 13 , wherein indicating the time of the transition from the each supply voltage level includes indicating a required minimum time duration of operating at the each supply voltage level before an indication of a supply voltage level other than the each supply voltage level can be transmitted.
15. The apparatus of claim 11 , wherein the control circuit comprises one or more state machines.
16. The apparatus of claim 11 , wherein the integrated circuit comprises a processor.
17. An apparatus comprising:
a memory to store voltage step information for each supply voltage level for a plurality of supply voltage levels in separate memory locations, wherein the memory locations for the respective voltage step information of each supply voltage level storing
a respective first step voltage for a step increase in voltage from the respective each supply voltage level, and
a respective second step voltage for a step decrease in voltage from the respective each supply voltage level,
means for operating an integrated circuit at a first supply voltage level in the plurality of supply voltage levels;
means for determining a second supply voltage level to be provided to the integrated circuit based on the respective step voltage information of the first supply voltage level;
means for transmitting, from the integrated circuit to a voltage regulator, an indication of the determined second supply voltage level to be provided to the integrated circuit;
means for receiving the second supply voltage level from the voltage regulator; and
means for operating the integrated circuit at the second supply voltage level.
18. The method of claim 17 , wherein one of the first step voltage and the second step voltage of the first supply voltage level represents a size of a voltage transition from the first voltage level.
19. The method of claim 17 , wherein the memory locations for the respective voltage step information of each supply voltage level further storing voltage step time information indicating a time of a transition from the each supply voltage level.
20. The method of claim 19 , wherein indicating the time of the transition from the each supply voltage level includes indicating a required minimum time duration of operating at the each supply voltage level before an indication of a supply voltage level other than the each supply voltage level can be transmitted.
21. An apparatus comprising:
a memory to store voltage step information for each supply voltage level for a plurality of supply voltage levels in separate memory locations, wherein the memory locations for the respective voltage step information of each supply voltage level storing
a respective first step voltage for a step increase in voltage from the respective each supply voltage level, and
a respective second step voltage for a step decrease in voltage from the respective each supply voltage level,
a means for providing, with a voltage regulator, a first supply voltage level to an integrated circuit;
means for determining a second supply voltage level to be provided to the integrated circuit based on the respective step voltage information of the first supply voltage level;
means for receiving, from the integrated circuit, voltage step information indicating the determined second supply voltage level to be provided to the integrated circuit by the voltage regulator;
a means for providing the second supply voltage level to the integrated circuit with the voltage regulator.
22. The apparatus of claim 21 , wherein one of the first step voltage and the second step voltage of the first supply voltage level represents a size of a voltage transition from the first voltage level.
23. The apparatus of claim 21 , wherein the memory locations for the respective voltage step information of each supply voltage level further storing voltage step time information indicating a time of a transition from the each supply voltage level.
24. The apparatus of claim 23 , wherein indicating the time of the transition from the each supply voltage level includes indicating a required minimum time duration of operating at the each supply voltage level before an indication of a supply voltage level other than the each supply voltage level can be transmitted.