Research And Design Of A Charging Management Scheme Supporting Fast Charging

With the rapid development of modern technology,the popularity of various of portable electronic devices is also increasing in various industries,and the functions of these devices are also becoming more diverse and intelligent.The superior performance of the lithiumion battery determines its versatility as an energy storage element in portable devices.With the enhancement of the performance and the improvement of energy consumption of electronic equipment,the charging management system has put forward more stringent requirements on charging speed,charging cost and safety.Therefore,it is greatly significant to study the lithium battery charge management system.In view of the problems that may exist in the current battery charging management system,such as low charging efficiency,inconsistent charging protocols,and low safety and reliability,a charging management solution that supports fast charging is proposed in this paper.First of all,in order to improve charging efficiency,this paper adopt a two-way topology and a precharging and constant current / constant voltage three-stage charging scheme;Secondly,in order to solve the problem of inconsistent charging protocols,this paper use a fast charging implementation module based on BC1.2 protocol.In the module,the charging port detection will be identified and input current will be limited so as to achieve compatibility with multiple charging protocols and fast charging;Finally,in order to improve safety and reliability of the system,this paper use a dynamic power management scheme so as to monitor the system status through ADC in time,then IIC transmits its information to an external host for communication,and optimizes the configuration of the system status to ensure system security and improve charging efficiency.This paper uses 0.18μm BCD technology to design a charge management system that supports fast charging.First,the dynamic power management module is simulated and verified,and the results show that the information sampling and data storage functions of the module are correct;Then,the overall function of the system is simulated and verified.The results show that when the system is in CHARGE mode,the input voltage is 5V,the battery voltage is in the range of 3V ～ 4.2V,the charging current can reach up to 3.6A,and the switching frequency is constant at 1.2MHz,the conversion efficiency of the system is up to 96%,the input voltage limiting loop works normally,and the input undervoltage latch and input overvoltage protection functions also works normally.In summary,the charge management system designed in this paper is a system that realizes fast charging under the premise that all functions of the charge circuit are working normally.