System and method to compensate for process and environmental variations in semiconductor devices

1. A method of optimizing operation of an integrated circuit (IC) comprised of devices and sub-circuits, the method comprising:

receiving in the IC electrical power and information on at least one of one or more operational parameters of the IC; and

adjusting one or more operating characteristics of at least one of the devices and sub-circuits in the IC based on the received information using a controller integrally formed on a shared die with the IC.

2. The method of claim 1 , wherein the IC comprises one or more environmental sensors to sense environmental conditions including one or more of temperature of the IC, voltage and current supplied to the IC, and wherein adjusting operating characteristics of at least one of the devices and sub-circuits further comprises receiving in the controller output signals from the one or more environmental sensors and adjusting operating characteristics of at least one of the devices and sub-circuits in response thereto.

3. The method of claim 1 , wherein the IC comprises on-chip test structures and comparators to measure and compare operating characteristics of the one or more devices and sub-circuits to reference values stored in the IC, and wherein adjusting operating characteristics of the one or more devices and sub-circuits further comprises receiving in the controller output signals from the on-chip test structures and comparators and adjusting operating characteristics of at least one of the devices and sub-circuits in response thereto.

4. The method of claim 1 , wherein the IC is one of a plurality of ICs on an undiced substrate, and wherein adjusting operating characteristics of at least one of the devices and sub-circuits comprises adjusting operating characteristics of at least one of the devices and sub-circuits to compensate for variations in operating characteristics of the one or more devices and sub-circuits across the substrate due to process variations across the substrate.

5. The method of claim 1 , wherein the one or more devices and sub-circuits for which the operating characteristics are adjusted comprise one or more power regulators, body-bias generators, current references, voltage references, current scaling circuits, delay-circuits, built-in-self-test (BIST) circuits and phase (PLLs).

6. The method of claim 5 , wherein the operating characteristics adjusted using the controller comprise one or more voltages, currents, time delays and frequency multiplication factors.

7. The method of claim 1 , wherein receiving in the IC electrical power and information on at least one of one or more operational parameters of the IC comprises receiving a clock signal.

8. The method of claim 1 , wherein the electrical power received in the IC comprises a reference voltage or reference current, and wherein adjusting one or more operating characteristics of at least one of the devices comprises adjusting one or more operating characteristics of at least one of the devices and sub-circuits in the IC based on the reference voltage or reference current.

9. An integrated circuit (IC) comprising:

a plurality of devices and sub-circuits;

environmental sensors to sense environmental conditions including one or more of a temperature of the IC, voltage, and current supplied to the IC;

a controller integrally formed on a shared die with the plurality of devices and sub-circuits to adjust operating characteristics of one or more of the plurality devices and sub-circuits in response to the sensed environmental conditions to meet one or more operational parameters for the IC;

memory to store reference values for one or more operational parameters for the IC; and

on-chip test structures and comparators electrically coupled to the controller to measure and compare one or more measured operational parameters for the IC to the stored reference values.

10. The IC of claim 9 , wherein the memory further stores operating characteristics of one or more of the plurality of devices and sub-circuits determined using the controller during an initial calibration to compensate for variations in operating characteristics of the plurality of devices and sub-circuits due to process variations across a substrate on which the IC was fabricated.

11. The IC of claim 9 , wherein the one or more of the plurality devices and sub-circuits for which the operating characteristics are adjusted comprise one or more power regulators, body-bias generators, current references, voltage references, current scaling circuits, delay-circuits, built-in-self-test (BIST) circuits and phase (PLLs).

12. The IC of claim 9 , wherein the IC further comprises a watchdog circuit to reset the controller if the controller fails to adjust operating characteristics of the one or more of the plurality devices and sub-circuits within a predetermined period of time.

13. A method of operating an integrated circuit (IC) comprising a memory core including metal-oxide-semiconductor (MOS) transistors, the method comprising:

receiving in the IC electrical power and a clock signal; and

controlling a body-bias regulator in the IC based on the received electrical power and clock signal using a controller integrally formed on a shared die with the IC to reduce subthreshold leakage from the MOS transistors in the memory core.

14. The method of claim 13 , wherein the IC includes one or more periphery logic devices including MOS transistors, and wherein the method further comprises controlling a periphery body-bias regulator to adjust saturation current (I DSAT ) of the MOS transistors in at least one of the periphery logic devices.

15. The method of claim 14 , wherein the IC includes a periphery power regulator through which power is supplied to the one or more periphery logic devices, and wherein the method further comprises controlling the periphery power regulator to compensate for timing shifts due to resistance-capacitance (RC) interconnect variations.

16. The method of claim 15 , wherein the IC includes a memory core power regulator through which power is supplied to the memory core, and wherein the method further comprises controlling the memory core power regulator to meet operational parameters for the IC including speed and subthreshold leakage.

17. The method of claim 16 , wherein the IC comprises one or more environmental sensors to sense environmental conditions including one or more of temperature of the IC, voltage and current supplied to the IC, and wherein the method comprises receiving in the controller output signals from the one or more environmental sensors and controlling the body-bias regulators, the periphery power regulator and the memory core power regulator in response thereto.

18. The method of claim 16 , wherein the IC is one of a plurality of ICs on an undiced substrate, and wherein the method comprises controlling the body-bias regulators, the periphery power regulator and the memory core power regulator to compensate for variations in operating characteristics of the MOS transistors in the memory core and periphery logic devices across the substrate due to process variations across the substrate.