Autonomic supply voltage compensation for degradation of circuits over circuit lifetime

Patent metadata

Field	Value
Publication number	US-10365702-B2
Application number	US-201715482917-A
Country	US
Kind code	B2
Filing date	Apr 10, 2017
Priority date	Apr 10, 2017
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

Over at least part of a lifetime of a product circuit, quiescent current to a product circuit is periodically measured. Over the part of the lifetime of the product circuit, voltage to the product circuit is periodically adjusted based on the monitored quiescent current. Methods, apparatus, and computer program product are disclosed. A calibration procedure may also be performed as part of manufacturing the product circuit, in order to provide values for the quiescent current and corresponding voltage to which the voltage should be adjusted.

First claim

What is claimed is:

1. A method, comprising:
periodically, over at least part of a lifetime of a product circuit, monitoring quiescent current to a product circuit, wherein periodically monitoring quiescent current comprises measuring at a measurement time quiescent current to the product circuit; and
periodically, over the part of the lifetime of the product circuit, increasing voltage output by a power supply to the product circuit based on the monitored quiescent current, wherein periodically increasing voltage output by the power supply to the product circuit based on the monitored quiescent current further comprises:
performing a comparison using the measured quiescent current with values stored in a table in order to determine whether one or more circuits in the product circuit have experienced degradation over time, wherein the values were stored in the table prior to the measurement time; and
increasing the voltage output by the power supply to the product circuit from a current voltage to a higher voltage based on the measured quiescent current.

2. The method of claim 1 , wherein:
measuring at a measurement time quiescent current to the product circuit further comprises:
stopping a system clock;
measuring the quiescent current to the product circuit;
storing a value of the quiescent current as a new value of quiescent current;
comparing the new value of the quiescent current with a previous value of the quiescent current taken at a previous measurement; and
restarting the system clock after voltage increase or after a determination no voltage increase is to be made; and

the periodically increasing the voltage is performed in response to the new value being less than the previous value, wherein increasing a voltage output by a power supply to the product circuit from a current voltage to a higher voltage based on the measured quiescent current meeting a criterion further comprises increasing the voltage output by the power supply to the product circuit from the current voltage to the higher voltage based on the new value of the quiescent current being less than the previous value of the quiescent current and based on the current voltage being less than or equal to a maximum voltage of the power supply.

3. The method of claim 1 , wherein increasing a voltage output by a power supply to the product circuit from a current voltage to a higher voltage based on the measured quiescent current further comprises increasing the voltage according to data stored in the table.

4. The method of claim 1 , wherein the method is performed for each one of multiple power domains in the product circuit.

5. An apparatus, comprising:
a product circuit;
a power supply and a voltage regulator; and
a controller configured to periodically, over at least part of a lifetime of a product circuit, monitor quiescent current to the product circuit, and to periodically, over the part of the lifetime of the product circuit, increase voltage output by the power supply to the product circuit based on the monitored quiescent current, wherein the controller comprises:
quiescent measurement circuitry configured to measure the quiescent current to the product circuit; and
a voltage compensation controller,

wherein the quiescent measurement circuitry periodically monitors quiescent current at least by measuring at a measurement time quiescent current to the product circuit; and
wherein the voltage compensation controller periodically increases the voltage output by the power supply to the product circuit based on the monitored quiescent current, at least by:
performing a comparison using the measured quiescent current with values stored in a table in order to determine whether one or more circuits in the product circuit have experienced degradation over time, wherein the values were stored in the table prior to the measurement time; and
causing the voltage output by the power supply to the product circuit to be increased from a current voltage to a higher voltage based on the measured quiescent current, at least by outputting a signal to the voltage regulator to cause the voltage regulator to output a signal to the power supply to cause the power supply to increase voltage to the higher voltage.

6. The apparatus of claim 5 , wherein the values were stored in the table prior to a first measurement of the quiescent current made in order to determine whether the one or more circuits in the product circuit have experienced degradation over time.

7. The apparatus of claim 5 , wherein the values were stored in the table in response to a calibration procedure performed by a factory as part of manufacturing the product circuit.

8. The apparatus of claim 7 , wherein the calibration procedure comprises the following:
stopping a system clock;
setting a selected voltage to a minimum voltage produced by the power supply;
setting a voltage to the product circuit at the selected voltage;
measuring a quiescent current to the product circuit at the selected voltage;
storing a representation of the quiescent current, corresponding to the selected voltage, in the table;
setting the selected voltage to a higher voltage;
continuing to set the voltage to the product circuit at the selected voltage, measuring, storing, and setting the selected voltage to a higher voltage until a maximum voltage of the power supply is reached.

9. The apparatus of claim 5 , wherein:
the controller is configured to stop a system clock;
the quiescent measurement circuitry is configured to measure the quiescent current to the product circuit and to store a value of the quiescent current as a new value of quiescent current;
the voltage compensation controller is configured to compare the new value of the quiescent current with a previous value of the quiescent current taken at a previous measurement and to increase the voltage output by the power supply to the product circuit from the current voltage to the higher voltage based on the new value of the quiescent current being less than the previous value of the quiescent current; and
the controller is configured to restart the system clock after voltage is increased or after a determination no voltage increase is to be made.

10. The apparatus of claim 9 , wherein the controller is configured to send an alarm in response to the maximum voltage of the power supply being reached.

11. The apparatus of claim 9 , wherein the controller is configured to determine the new value of the quiescent current is greater than the previous value of the quiescent current and to send an alarm in response to the new value of the quiescent current is greater than the previous value of the quiescent current.

12. The apparatus of claim 9 , wherein the controller is further configured, prior to stopping the system clock, to send a signal toward an operating system to inform the operating system the system clock will be stopped.

13. The apparatus of claim 9 wherein:
the quiescent current measuring circuitry is configured to store, along with the value of the new value of quiescent current, a time stamp indicating a measurement time of the new value of the quiescent current and a value of a current supply voltage at which the new value of the quiescent current was determined; and
the quiescent current measuring circuitry is configured to compare the new value of the quiescent current with the previous value of the quiescent current taken at a previous measurement uses measurement times for each of the new value and previous value of the quiescent current.

14. The apparatus of claim 5 , wherein increasing the voltage output by the power supply to

Assignees

• IBM

Inventors

• Cher Chen-Yong
• Chuang Pierce I
• Jenkins Keith A
• Linder Barry

Classifications

• G06F1/3237

  by disabling clock generation or distribution · CPC title

• G01R31/2832

  Specific tests of electronic circuits not provided for elsewhere (G01R31/2801, G01R31/316 take precedence) · CPC title

• G06F1/3206 Primary

  Monitoring of events, devices or parameters that trigger a change in power modality · CPC title

• G06F1/3296

  by lowering the supply or operating voltage · CPC title

• G01R19/0092

  Measuring current only · CPC title