Design Of A Linear Charge Management IC Lithium Battery

Electronic products consumption present prosperity gradually, at the same time the market, the demand for lithium battery is also growing.With low cost, simple structure, high integration, high precision, low power consumption characteristics of lithium battery management chip has a broad application prospect.This paper designed a model with a three-stage charging of the lithium battery management chip.In the aspect of circuit design, firstly analyzes the lithium ion battery management chip system architecture and workflow.Second, the research is mainly focused on the second-order temperature compensation of bandgap voltage reference source circuit,compared with the traditional bandgap reference voltage source rejection ratio improved the precision of temperature and temperature.Once again, to the current benchmark, the design of the protection circuit modules of research, the low consumption is largely based on the threshold MOS tube and no op-amp comparator two technologies.Finally, introduces the system control module, the time delay module, as well as other detection module design, and has made the simulation of the system.This paper adopts CSMC on China 0.5 ?m N well process, circuit design and simulation in Cadence software platform. The simulation results show that the design of the chip-40-85, in the temperature range, in different process corners, trickle charge phase current maximum value is 0.102 A, the minimum value is 0.099 A. Constant current charging stage current maximum value is 1.019 A, the minimum value is 0.994 A. The constant voltage charging phase voltage maximum value is 4.26 V, the minimum value is 4.17 V. Temperature coefficient of two order bandgap reference is 8.33ppm/ ??In addition, over temperature,over current, over charge and over discharge protection circuit works well, can well protect the Li ion battery.