Bootstrap Gate Driver Load-Adaptive High-Side Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional bootstrap gate drivers in synchronous rectification circuits cannot effectively disable the high-side transistor during light-loading states, leading to inefficient power conversion due to ongoing switching losses.
Innovation Solution
A bootstrap gate driver with a load indication unit, a bootstrap gate-drive unit, and a drive-control unit that enables or disables the high-side driving path based on load state, allowing the high-side transistor to be inactivated during light-loading states, thereby improving efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If both high-side and low-side transistors are controlled by the same PWM signal for simplicity, then device complexity is reduced, but the ability to independently control rectification mode is lost
Solution Approach 1:
The gate driver segments the control of high-side and low-side transistors into independent paths. The low-side transistor continues to be controlled by the original PWM signal, while the high-side transistor is controlled by a separately generated drive signal that can be independently enabled or disabled based on load conditions. This segmentation allows flexible control of synchronous rectification without complicating the overall control architecture.
Solution Approach 2:
The gate driver introduces an intermediary control mechanism that mediates between the single PWM input and the dual transistor control requirements. By generating a conditional enable signal for the high-side transistor based on load detection, the system achieves adaptable rectification mode control while maintaining relatively simple device structure.
Data Source
AI summary
A bootstrap gate driver including a load indication unit, a bootstrap gate-drive unit and a drive-control unit is provided. The load indication unit is configured to generate a load indication signal in response to a state of a load. The bootstrap gate-drive unit is configured to drive a switch-transistor circuit in response to an inputted pulse-width-modulation (PWM) signal, wherein the switch-transistor circuit has a high-side driving path and a low-side driving path. The drive-control unit is coupled to the load indication unit and the bootstrap gate-drive unit, and configured to enable or disable the high-side driving path in response to the load indication signal. In the invention, the operation of the low-side driving path is not affected by enabling or disabling the high-side driving path.