Switching Regulator Charge Sharing for Bootstrap Gate Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Switching regulators face challenges in ensuring a sufficient gate-source voltage for switching elements across multiple conversion modes, which affects their performance and efficiency.
Innovation Solution
The design incorporates a switching regulator with a first and second switching circuit, each including a transistor, flying capacitor, and bootstrap capacitor, along with a charge sharing circuit that selectively forms charge sharing paths between these components in response to conversion modes, ensuring a sufficient gate-source voltage for transistors through boosting and charging mechanisms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple conversion modes are supported with multiple switching elements, then the switching regulator can generate various levels of supply voltages, but ensuring sufficient gate-source voltage for all switching elements becomes more difficult
Solution Approach 1:
The first flying capacitor serves multiple functions: it acts as a flying capacitor during buck operation and as a bootstrap capacitor for the second transistor during boost operation. This multi-functionality ensures that sufficient gate-source voltage is available for both switching transistors across different conversion modes without requiring separate dedicated capacitors for each function.
Solution Approach 2:
The patent combines the bootstrap capacitor function with the flying capacitor by configuring the first flying capacitor to serve as the bootstrap capacitor for the second transistor. This merging of functions reduces the total number of capacitors needed while ensuring that the gate-source voltage requirement is met for both switching elements in both buck and boost modes.
2Reliability
If separate bootstrap capacitors are provided for each switching element, then sufficient gate-source voltage can be ensured, but the number of circuit components increases
Solution Approach 1:
The first flying capacitor is designed to perform dual functions: operating as a flying capacitor during buck mode and as a bootstrap capacitor during boost mode. This eliminates the need for a separate dedicated bootstrap capacitor for the second transistor, thereby reducing the total component count while maintaining reliable gate-source voltage supply for both switching elements.
Solution Approach 2:
The patent merges the bootstrap capacitor function into the existing flying capacitor structure. By configuring the first flying capacitor to serve as the bootstrap capacitor for the second transistor, the design consolidates components and reduces circuit complexity while ensuring that both transistors receive adequate gate-source voltage in their respective operating modes.
3Reliability
If more circuit components are used to ensure proper voltage boosting, then gate-source voltage can be maintained, but circuit miniaturization is hindered
Solution Approach 1:
The first flying capacitor is designed to perform dual functions: operating as a flying capacitor during buck mode and as a bootstrap capacitor during boost mode. This eliminates the need for a separate dedicated bootstrap capacitor for the second transistor, thereby reducing the total component count and enabling circuit miniaturization while maintaining reliable gate-source voltage supply for both switching elements.
Solution Approach 2:
The patent merges the bootstrap capacitor function into the existing flying capacitor structure. By configuring the first flying capacitor to serve as the bootstrap capacitor for the second transistor, the design consolidates components and reduces circuit size while ensuring that both transistors receive adequate gate-source voltage in their respective operating modes.
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
This configuration enhances the performance of switching regulators by ensuring sensitive response to control signals and minimizing circuit components, leading to improved efficiency and miniaturization.
Implementation Method 1
a first bootstrap capacitor that boosts a gate voltage of the first transistor
Implementation Method 2
a second bootstrap capacitor that boosts a gate voltage of the second transistor
Implementation Method 3
a first flying capacitor that shares charge with the second bootstrap capacitor
Data Source
AI summary
A switching regulator generates an output voltage from an input voltage and includes; a charge sharing circuit that selectively forms one of a first charge sharing path between a first flying capacitor and a second bootstrap capacitor and a second charge sharing path between a second flying capacitor and a first bootstrap capacitor based on first and second conversion modes.