Voltage Regulator Feedback Compensation for AVP Loadline Errors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Voltage regulators with adaptive voltage positioning (AVP) face performance degradation due to the inability to accurately sense load current, leading to output voltage deviations and undershoots during dynamic voltage identification and phase number changes, as the inductor current approximation fails to accurately represent the load current.
Innovation Solution
A compensation circuit is introduced within the feedback loop to generate a compensation signal based on sensed inductor current, which is injected into the feedback signal to correct output voltage deviations and undershoots, using parameters such as output capacitance and slew rate to adjust the compensation current.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If inductor current is used to approximate load current in AVP implementation, then load information can be obtained without direct load current sensing, but the approximation fails during dynamic events causing output voltage regulation performance degradation
Solution Approach 1:
The patent introduces a compensation circuit as an intermediary component that processes the inductor current signal and generates a compensation output signal. This mediator bridges the gap between the easily measurable inductor current and the desired load current representation, correcting the approximation errors during dynamic events without requiring direct load current sensing
Solution Approach 2:
The compensation circuit dynamically adjusts the compensation output signal based on changing operating conditions, specifically responding to dynamic events like phase number changes and voltage transitions. By changing the compensation parameter in real-time, the system maintains accurate voltage regulation despite the inherent approximation of using inductor current instead of direct load current sensing
2Measurement precision
If a compensation circuit is added to correct output voltage deviations, then voltage regulation accuracy is improved, but the device complexity increases
Solution Approach 1:
The compensation circuit is merged with the existing feedback loop structure, where the compensation output signal is combined with the feedback signal from the loadline. This integration allows the compensation function to be added without creating a completely separate control path, thereby improving voltage regulation accuracy while limiting the increase in overall device complexity
Solution Approach 2:
The compensation circuit operates within the feedback loop, using the feedback signal containing loadline information to generate the compensation output signal. This feedback mechanism allows the system to automatically correct output voltage deviations based on actual operating conditions, improving regulation accuracy while using the existing feedback infrastructure to minimize additional complexity
Data Source
AI summary
A feedback loop circuit of a voltage regulator includes a loadline and a compensation circuit. The loadline generates a feedback signal according to a sensed current signal that provides information of an inductor current of the voltage regulator, and outputs the feedback signal to a controller circuit of the voltage regulator for regulating an output voltage of the voltage regulator. The compensation circuit generates a compensation signal to compensate for a deviation of the output voltage, wherein the feedback signal generated from the loadline is affected by the compensation signal.