Minimum Energy Tracking Loop With Oscillator-Based Energy Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing minimum energy tracking loops for battery-powered devices face errors in energy measurement due to changes in supply voltage and limitations in accurately measuring low energy consumption, particularly in ultra-low power devices like implantable medical devices, where the error increases with small voltage changes and is exacerbated by comparator offsets, leading to suboptimal energy management.
Innovation Solution
A minimum energy tracking loop apparatus that includes an oscillator to adjust clock frequency, a voltage regulator for constant power supply, an energy sensing unit to calculate proportional energy, a minimum energy finder using coarse and fine tracking loops, and a digital-analog converter to convert the minimum energy point into an analog reference voltage, enabling accurate energy sensing and hierarchical tracking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the supply voltage is intentionally changed to measure total energy consumed by the load system, then the energy measurement can be performed, but the measurement error increases proportionally with the amount of changed supply voltage
Solution Approach 1:
The patent introduces an intermediary measurement approach using an oscillator that converts energy consumption into frequency changes. Instead of directly measuring voltage changes which introduce errors, the oscillator frequency serves as an intermediary parameter that accurately reflects energy consumption without the proportional errors associated with direct voltage measurement methods.
Solution Approach 2:
The patent replaces the traditional voltage-based measurement system with an oscillator-based frequency measurement system. This substitution eliminates the measurement errors inherent in voltage change methods, as frequency measurements are not subject to the same proportional errors when supply voltage is changed.
2Manufacturing precision
If the voltage step is set small (10 mV or lower) to find accurate minimum energy operating level, then the energy control precision is improved, but the existing loop becomes unstable due to measurement errors
Solution Approach 1:
The oscillator acts as an intermediary that enables stable detection of small voltage changes. By converting energy consumption into frequency measurements, the system can detect minute changes corresponding to 10 mV or lower voltage steps without the measurement errors that would otherwise cause loop instability.
Solution Approach 2:
The patent changes the measurement parameter from direct voltage measurement to frequency measurement. This parameter transformation allows the system to achieve high voltage control precision with small steps while maintaining loop stability, as frequency measurements provide the necessary measurement accuracy without the errors that plague voltage-based methods.
3Use of energy by moving object
If the supply voltage is scaled down to reduce switching energy, then the switching energy is quadratically decreased, but the leakage current increases proportionally
Solution Approach 1:
The patent implements a feedback mechanism through the oscillator that continuously monitors energy consumption and provides information about the minimum energy point. This feedback enables the system to dynamically adjust operating parameters to achieve optimal energy efficiency, balancing switching energy reduction with leakage energy management by identifying the true minimum energy operating point.
Data Source
AI summary
Disclosed are an apparatuses and methods for minimum energy tracking loop that includes an oscillator to imitate a threshold path of a load system and automatically adjust a clock frequency as a supply voltage to the load system is changed, a voltage regulator configured to supply a power, an energy sensing unit which is connected to the oscillator and the voltage regulator and calculates a proportional energy proportional to a total energy consumed by the load system at a specific supply voltage, a minimum energy finder to find a minimum energy point of the load system by monitoring the calculated proportional energy proportional to the total energy at a plurality of supply voltages, a buck converter to supply a power to the load system with a supply voltage at which the load system operates with a minimum energy when the minimum energy point is found in the minimum energy finder.