Capacitor Bootstrap Buck Converter for Single Cell Voltage Regulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing voltage regulation solutions for electronic devices, such as two-stage architectures and SEPIC converters, suffer from inefficiencies, large size, high output voltage ripple, and poor transient response due to the need to generate voltage rails above or below the input voltage range, particularly when using single lithium ion cells.
Innovation Solution
A buck boost converter configuration utilizing a capacitor pump and buck converter with a capacitive doubler arrangement, which applies input voltage through switching circuitry to generate common 5/3.3 volt system rails with low output ripple, employing 5 switches and controlling transistors to manage input voltage levels efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If two-stage architecture or SEPIC converter is used to generate voltage rails above or below input voltage, then voltage regulation capability is improved, but device size and complexity increase
Solution Approach 1:
The patent combines the boost and buck functions into a single integrated converter stage, merging two separate voltage regulation functions into one device. This eliminates the need for separate boost and buck converters, reducing overall device size and complexity while maintaining the ability to generate voltage rails both above and below the input voltage range.
Solution Approach 2:
The converter is designed with universal functionality to operate in multiple modes: boost mode for generating voltage above input, buck mode for generating voltage below input, and buck-boost mode for extended range regulation. This multi-functional design eliminates the need for separate dedicated boost and buck converters, reducing device size while maintaining versatility.
2Adaptability or versatility
If traditional voltage regulation circuits are used, then voltage rails can be generated, but output voltage ripple increases
Solution Approach 1:
The patent introduces an intermediary capacitor network that acts as a voltage smoothing element between the switching stage and output. This capacitor bootstrap circuitry filters the voltage ripple generated by the switching operation, providing clean regulated output voltage while maintaining the ability to generate various voltage rails.
3Productivity
If H-bridge topology is used for buck/boost capability, then single-step voltage regulation is achieved, but RMS switch current increases
Solution Approach 1:
The patent optimizes the switching parameters and duty cycle control to minimize RMS current through the switches. By carefully controlling the timing and duration of switch conduction in the capacitor bootstrap circuit, the design achieves efficient single-step buck/boost operation with reduced RMS switch current compared to traditional H-bridge topologies.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution provides improved voltage regulation with low output ripple and comparable RMS switch current to H-bridge topologies, enabling efficient generation of common voltage rails from a single lithium ion cell while minimizing size and control complexity.
Implementation Method 1
A buck boost converter configuration utilizes a capacitor pump and buck converter with a capacitive doubler arrangement
Implementation Method 2
buck converter portion (104) having a switch (210)串联 with an inductor (214)
Data Source
AI summary
A buck boost voltage converter circuit has a capacitor pump circuit for boosting an input voltage in a first mode of operation when an input voltage is below a desired voltage level. A buck converter circuit provides the output voltage responsive to the boosted input voltage from the capacitor pump circuit in the first mode of operation and provides the output voltage responsive to the input voltage in a second mode of operation when the input voltage is above the desired voltage level.