Battery Charging Circuit Control for CPU Transient Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery charging circuits face challenges in meeting the increased instantaneous power demands of CPUs during performance boosts, leading to potential under voltage shutdowns and instability.
Innovation Solution
A control circuit and method for a battery charging circuit that includes a switching circuit with an inductor, a charging current control loop, an amplitude limiting circuit, an inductor current control loop, and a system voltage control loop, which provide feedback signals to manage charging current, inductor current, and system voltage, ensuring stable operation by limiting inductor current and maintaining constant voltage or current levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the battery charging circuit increases the maximum input current level to meet CPU instantaneous power demands, then the power delivery capability is improved, but the system stability deteriorates due to potential under voltage shutdowns
Solution Approach 1:
The patent implements a feedback control mechanism where the controller monitors the input voltage level and dynamically adjusts the inductor current reference signal. When input voltage drops below a threshold, the controller limits the inductor current to prevent under voltage shutdown, thereby maintaining system stability while still allowing high current operation under normal conditions
Solution Approach 2:
The system dynamically adjusts the inductor current reference signal based on real-time input voltage conditions. The controller switches between different current reference levels depending on whether the input voltage is above or below the threshold, enabling the system to adapt its power delivery capability to current operating conditions
2Power
If the battery charging circuit allows high inductor current to meet instantaneous power demands, then the power delivery capability is improved, but the transient response time worsens due to system instability
Solution Approach 1:
The feedback control loop continuously monitors input voltage and adjusts the inductor current reference signal accordingly. This feedback mechanism enables the system to respond quickly to voltage drops by immediately limiting current, achieving fast transient response while preventing instability
Solution Approach 2:
The controller is configured with a predetermined voltage threshold and corresponding current reference signal. When the input voltage approaches this threshold, the controller proactively adjusts the current reference signal to prevent under voltage shutdown, enabling preemptive action rather than reactive correction
Data Source
AI summary
A battery charging circuit receives an input current, and provides a system voltage and a charging current to charge a battery. A control circuit used to control the battery charging circuit has a charging current control loop providing a compensation signal, an inductor current control loop providing a first loop control signal, and a system voltage control loop providing a second loop control signal. The control circuit provides an inductor current reference signal based on the compensation signal and a designed maximum input current level. And the control circuit provides a control signal based on the first loop control signal the second loop control signal to control the battery charging circuit.