Temperature ramp control for integrated circuit chips
A circuit system includes a circuit board including a plurality of integrated circuit (IC) chips. The circuit board is configured to be immersed in a two-phase cooling fluid. The circuit system includes a controller. The controller is configured to, in a control process: obtain temperature data indicative of respective internal temperatures of the plurality of IC chips, predict respective future internal temperatures of the plurality of IC chips based on the respective internal temperatures, and adjust clock frequencies and power supply voltages of the plurality of the IC chips such that the predicted respective future internal temperatures are within a target temperature range. A clock frequency of a first IC chip of the plurality of IC chips is adjusted to be different from a clock frequency of a second IC chip of the plurality of IC chips.
1 . A circuit system, comprising:
a circuit board comprising a plurality of integrated circuit (IC) chips, wherein the circuit board is configured to be immersed in a two-phase cooling fluid; and
a controller communicably coupled to the circuit board, wherein the controller is configured to:
use a first control method to adjust at least one of clock frequencies or power supply voltages of the plurality of the IC chips to cause a temperature of the two-phase cooling fluid to increase,
obtain temperature data indicative of the temperature of the two-phase cooling fluid, and
based on the temperature of the two-phase cooling fluid satisfying a target condition, switch from the first control method to a second control method, and use the second control method to adjust at least one of the clock frequencies and the power supply voltages of the plurality of the IC chips.
2 . The circuit system of claim 1 , wherein the target condition comprises that the temperature of the two-phase cooling fluid is in a target temperature range.
3 . The circuit system of claim 1 , wherein the condition comprises at least one of:
the temperature of the two-phase cooling fluid is stable or non-increasing, or
a rate of increase of the temperature of the two-phase cooling fluid is below a threshold value.
4 . The circuit system of claim 1 , wherein the first control method comprises:
predicting respective future internal temperatures of the plurality of IC chips; and
adjusting the clock frequencies and the power supply voltages of the plurality of the IC chips such that the predicted respective future internal temperatures are within a target temperature range.
5 . The circuit system of claim 4 , wherein the first control method is iterative, and
wherein, for a same iteration of the first control method, a predicted change in internal temperature of a first IC chip of the plurality of IC chips is different from a predicted change in internal temperature of a second IC chip of the plurality of IC chips.
6 . The circuit system of claim 1 , wherein the second control method comprises a dynamic
voltage and frequency scaling (DVFS) algorithm.
7 . The circuit system of claim 1 , wherein the controller is configured to modify a target temperature range of the plurality of IC chips based on the temperature of the two-phase cooling fluid satisfying the condition.
8 . The circuit system of claim 1 , wherein the controller is configured to:
use the first control method when the two-phase cooling fluid is in a convection regime, and
use the second control method when the two-phase cooling fluid is in a regime in which heat transfer is based primarily on liquid-gas phase transitions by the two-phase cooling fluid.
9 . The circuit system of claim 1 , wherein the second control method is configured to cause temperatures of the plurality of IC chips to be within a target temperature range.
10 . The circuit system of claim 1 , wherein the first control method comprises a feed-forward method.
11 . The circuit system of claim 1 , wherein the controller is configured to use the second control method when the two-phase cooling fluid is boiling.
12 . The circuit system of claim 1 , wherein a clock frequency of a first IC chip of the plurality of IC chips is adjusted to be different from a clock frequency of a second IC chip of the plurality of IC chips.
13 . The circuit system of claim 1 , comprising the two-phase cooling fluid, wherein the circuit board is immersed in the two-phase cooling fluid.
14 . The circuit system of claim 1 , wherein the controller is mounted in a common enclosure with the circuit board and is configured to be immersed in the two-phase cooling fluid.
15 . The circuit system of claim 1 , wherein the controller is configured to, prior to using the using the first control method:
sense at least one system characteristic, the at least one system characteristic comprising at least one of an amount of the two-phase cooling fluid or a level of contamination of the two-phase cooling fluid; and
based on the at least one system characteristic being in a target range, initiating usage of the first control method.
16 . A circuit system control method comprising:
adjusting, using a first control method, at least one of clock frequencies or power supply voltages of a plurality of the integrated circuit (IC) chips embedded in a circuit board immersed in a two-phase cooling fluid, wherein the adjusting causes a temperature of the two-phase cooling fluid to increase;
obtaining temperature data indicative of the temperature of the two-phase cooling fluid; and
based on the temperature of the two-phase cooling fluid satisfying a target condition, switching from the first control method to a second control method, and adjusting at least one of the clock frequencies or the power supply voltages of the plurality of the IC chips using the second control method.
17 . The circuit system control method of claim 16 , wherein the target condition comprises at least one of:
the temperature of the two-phase cooling fluid is in a target range,
the temperature of the two-phase cooling fluid is stable or non-increasing, or
a rate of increase of the temperature of the two-phase cooling fluid is below a threshold value.
18 . The circuit system control method of claim 16 , wherein the first control method comprises a feed-forward method, and
wherein the second control method comprises a dynamic voltage and frequency scaling (DVFS) algorithm.
19 . The circuit system control method of claim 16 , comprising:
adjusting at least one of the clock frequencies or the power supply voltages using the first control method when the two-phase cooling fluid is in a convection regime, and
adjusting at least one of the clock frequencies or the power supply voltages using the second control method when the two-phase cooling fluid is in a regime in which heat transfer is based primarily on liquid-gas phase transitions by the two-phase cooling fluid.
20 . The circuit system control method of claim 16 , wherein using the first control method comprises:
predicting respective future internal temperatures of the plurality of IC chips; and
adjusting the clock frequencies and the power supply voltages of the plurality of the IC chips such that the predicted respective future internal temperatures are within a target temperature range.