Voltage Regulator Output Sense Current for Faster Load Transients
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Power management integrated circuits (PMICs) face challenges in maintaining output voltage regulation during load attacks, leading to voltage dips due to increased current demand, which existing regulators struggle to compensate effectively.
Innovation Solution
A voltage regulator design that utilizes an output sense current, where a sense capacitor and current amplifier work together to generate and amplify a sense current proportional to the output capacitor current, allowing for earlier detection of load changes and faster adjustment of the output voltage, thereby improving transient response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a conventional voltage regulator is used, then the circuit is simple, but the transient response is slow and voltage dips occur during load attacks
Solution Approach 1:
The sense capacitor senses the output capacitor current before the voltage dip occurs, providing advance warning of load attacks. This preliminary detection allows the control stage to prepare compensation action in advance, improving transient response without requiring complex additional circuitry
Solution Approach 2:
The sense capacitor acts as an intermediary element that couples the output capacitor current to the control stage. It transfers the current information (proportional to load attack magnitude) to the control stage, enabling faster response without directly complicating the main regulator circuit
2Reliability
If the output capacitor size is increased to reduce voltage undershoot, then voltage regulation improves, but the component size and cost increase
Solution Approach 1:
The sense capacitor provides feedback about the output capacitor current to the control stage. This feedback mechanism allows the regulator to dynamically adjust and compensate for voltage dips caused by load attacks, achieving good voltage regulation with a smaller output capacitor than would be required in a conventional regulator without such feedback
Data Source
AI summary
Certain aspects of the present disclosure generally relate a regulator. For example, the regulator may include a control stage, a sense capacitor having first and second terminals, the first terminal coupled to an output of the voltage regulator, and a current amplifier having an input coupled to the second terminal of the sense capacitor and an output coupled to the control stage. The control stage of the regulator may adjust the output voltage of the regulator based at least in part on a current generated by the current amplifier.