Integrated Charger Circuit Merging Switching and Direct Charging Modes
Solution Overview
Problem
Prior charger circuits face low power conversion efficiency due to 2-stage conversion, high temperature issues in compact devices, and complex control schemes due to separate integrated circuits for switching and direct charging modes, leading to limited charging current and increased costs.
Innovation Solution
A charger circuit integrating a power delivery unit, conversion switch circuit, front stage switch, direct charging switch, and control circuit to operate in both switching and direct charging modes, with parasitic body current blocking and integrated packaging for simplified control and reduced size and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If 2-stage power conversion is used (adaptor + switching conversion circuit), then power conversion can be achieved, but power conversion efficiency is low
Solution Approach 1:
The patent merges the adaptor function and switching conversion circuit function into a single integrated charger circuit. The integrated circuit includes both the switching conversion circuit for voltage conversion and the load switch for direct charging, eliminating the need for separate adaptor and converter stages, thereby reducing energy loss and improving overall power conversion efficiency.
2Loss of time
If high constant charging current is used, then charging time is shortened, but temperature of switching conversion circuit becomes too high
Solution Approach 1:
The patent implements dynamic charging mode switching between switching charging mode and direct charging mode based on real-time conditions. The control circuit monitors temperature and charging requirements, dynamically selecting the appropriate mode: using switching conversion when high current is needed but temperature is acceptable, and switching to direct charging when temperature rises, thereby enabling high-speed charging while controlling temperature.
3Adaptability or versatility
If switching conversion circuit and load switch are manufactured as separate integrated circuits, then functionality is complete, but control scheme becomes complex and cost increases
Solution Approach 1:
The patent integrates the switching conversion circuit and load switch into a single integrated circuit device. This unified design includes all necessary components (switching elements, inductor, control circuit) within one chip, simplifying the control scheme by eliminating inter-chip communication requirements and reducing the number of external components needed, while maintaining both switching and direct charging functionalities.
Data Source
AI summary
A charger circuit for providing a charging power to a battery includes a power delivery unit and a power conversion circuit. The power conversion circuit includes at least one conversion switch coupled to an inductor, a front stage switch conducting a DC power generated by the power delivery unit to generate a mid-stage power, and a direct charging switch. In a switching charging mode, the conversion switch converts the mid-stage power to the charging current onto a charging node. In a direct charging mode, the power delivery unit regulates the DC current, and the front stage switch and the direct charging switch conduct the DC current onto the charging node. The body diodes of the front stage switch and the direct charging switch are reversely coupled, and the body diodes of the front stage switch and the conversion switch are reversely coupled, for blocking the parasitic body current.