Multi-domain PVT Tracking for Heterogeneous SoC Power Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for power reduction in large heterogeneous system-on-a-chip (SoC) integrated circuits face challenges such as high complexity, difficulty in adapting to new designs, high cost, and lost performance due to the need for multiple central controllers and PVT monitors across various supply domains, which results in power and area overhead that can negate power savings.
Innovation Solution
A multi-domain heterogeneous process-voltage-temperature tracking system that uses performance sensors and a core power reduction controller to dynamically adjust supply voltages and clock frequencies across multiple supply domains, allowing for efficient power management without the need for multiple central controllers, by collecting and processing measurements from performance sensors spread across the SoC to determine optimal voltage levels for each domain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If multiple central controllers and PVT monitors are used across various supply domains to track process, voltage, and temperature, then power reduction can be achieved, but power and area overhead increase which can negate power savings
Solution Approach 1:
The patent merges the functions of multiple central controllers and PVT monitors into a unified performance sensor system. Instead of having separate controllers for each supply domain, a single core power reduction controller collects performance measurements from multiple performance sensors distributed across different supply domains and heterogeneous circuit types, consolidating control functions to reduce overhead.
Solution Approach 2:
The performance sensors are designed to be universal and heterogeneous, capable of measuring performance across multiple supply domains and different circuit types (high-speed, high-density, etc.). This multi-functional approach eliminates the need for domain-specific sensors and controllers, reducing overall system complexity while maintaining comprehensive tracking capability.
2Measurement precision
If traditional Process Voltage Scaling with Fmax vectors is used to track supply domains, then voltage adjustment can be achieved, but test time cost increases and temperature tracking is not possible
Solution Approach 1:
The performance sensors continuously self-measure performance characteristics during normal operation without requiring external test equipment or test time. The sensors automatically collect performance data across process, voltage, and temperature variations, enabling real-time tracking without adding to production test time costs.
Solution Approach 2:
The system performs periodic performance measurements during normal operation rather than requiring extensive one-time testing. By continuously or periodically collecting performance data during operational phases, the system achieves comprehensive process tracking without extending manufacturing test time.
3Ease of manufacture
If process binning with coarse grained approaches is used, then manufacturing complexity is reduced, but manufacturing precision and performance optimization are compromised
Solution Approach 1:
The system dynamically adjusts supply voltages based on real-time performance measurements from multiple performance sensors, moving away from static coarse-grained binning. This dynamic approach allows fine-grained optimization of each supply domain while maintaining manageable manufacturing complexity through automated control.
Solution Approach 2:
The system changes operating parameters (supply voltages) based on measured performance characteristics, enabling precise optimization without requiring complex manufacturing binning. By adjusting voltages according to actual performance data, the system achieves fine-grained control while keeping manufacturing processes simple.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The systems and method described herein provide efficient (e.g., low power and low area) means to track performance in numerous supply domains with heterogeneous circuits that are used in a large system-on-a-chip integrated circuit (SoCs). The heterogeneous circuits can include circuits made with different devices, different cell libraries, and different hard macros that are in different power supply domains. Performance measurements from performance sensors (or process-voltage-temperature (PVT) sensors) that are spread about the SoC are collected and processed to determine voltage levels for each of the supply domains. A single controller can receive can determine voltage levels for a whole SoC. The performance sensors are connected to the controller by a scan chain. The technique is flexible and can be easily adapted for use in SoCs with different power supply domains and types of circuits.