Digital Undervoltage Detection Using Ring Oscillator Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated circuits face challenges in balancing performance, power consumption, and thermal output due to increased transistor density and decreased supply voltages, which can lead to undervoltage conditions affecting operational stability.
Innovation Solution
The integration of sensors with first and second ring oscillators, each providing frequency information to a computation circuit to calculate voltages, and comparison circuitry to detect voltage changes, enabling undervoltage detection and correction through control circuitry adjustments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the number of transistors per unit area is increased, then the processing power and functionality of the IC is improved, but the supply voltage decreases and thermal output increases
Solution Approach 1:
The IC is divided into multiple power domains with different voltage levels, allowing different regions to operate at optimal voltages for their specific functions while managing overall thermal output
Solution Approach 2:
The supply voltage is made dynamically adjustable through voltage scaling techniques, allowing the IC to operate at lower voltages when full performance is not needed, thereby reducing thermal output while maintaining processing capability
2Use of energy by moving object
If the supply voltage is decreased, then the power consumption is reduced, but undervoltage conditions occur affecting operational stability
Solution Approach 1:
A voltage monitoring subsystem continuously monitors the supply voltage and provides feedback to control logic, which can detect undervoltage conditions and trigger appropriate responses such as activating brownout reset or adjusting operational parameters
Solution Approach 2:
The system performs preliminary voltage detection and evaluation before critical undervoltage conditions occur, allowing preventive actions to be taken such as activating backup power sources or adjusting load distribution
3Reliability
If voltage monitoring is performed using a separate analog power supply, then isolation from voltage variations is improved, but device complexity increases
Solution Approach 1:
The monitoring subsystem is designed to operate from the same digital power supply as the functional circuitry, allowing it to monitor multiple voltage domains simultaneously and serving multiple functions including voltage detection, brownout detection, and thermal management coordination
Solution Approach 2:
The voltage monitoring functionality is merged with the existing digital power supply infrastructure, eliminating the need for separate analog power supply rails and reducing overall system complexity while maintaining monitoring effectiveness
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method and apparats for undervoltage detection and correction is disclosed. An IC includes sensors implemented in various functional circuit blocks. The sensors are implemented using ring oscillators, and may be characterized by a polynomial. The sensors are used to monitor a supply voltage provided to a corresponding functional unit. The sensors provide information indicative of the voltage on the supply voltage node over successive clock cycles. Comparison circuitry may be used to compare the detected voltage to one or more voltage thresholds, while delta comparison circuitry may be used to determine a slope, or rate of change of the voltage. Based on comparisons performed by the comparison circuitry and the delta comparison circuitry, control circuitry may determine if one or more voltage correction actions are to be taken in order to bring the voltage on the supply node into a specified range.