动力电池管理SoC采集前端及其ΣΔADC设计

Design of Acquisition Front-end and Σ-ΔADC in Battery Management SoC

为保证新能源汽车动力电池高效安全,其电池管理系统BMS核心芯片的采集前端需要实现高精度电压检测.因此,沿着从系统到芯片的设计思路,首先对采集前端进行系统级设计验证,提出新型采集前端结构,实现多通道电压高精度同步检测,电池单体电压检测误差小于5mV,精度为0.15%.然后在芯片级设计了高精度采集前端的关键模块Σ-ΔADC调制器,完成行为级仿真,电路和版图设计仿真,后仿真结果显示,调制器有效位数达到16.58位,信噪比达101.6dB,达到了电池管理芯片采集前端高精度ADC设计需求.系统级高精度采集前端电路的实现验证和核心ADC调制器的设计为电池管理芯片高精度采集前端的实现做了研究准备.

To guarantee the safety and efficiency of new energy automobiles, the acquisition front-end circuit of battery management IC requires high precision voltage detection. Therefore, using IC design methodology of System to Chip, system-level design and verification are carried out first. Based on new acquisition front-end structure, high-precision multi-channel voltage synchronous detection is achieved, cell voltage detection error is less than 5mV, and accuracy is about 0. 15%. Then, ∑-△ADC modulator is designed, which is the key module of chip-level high- precision acquisition front-end circuit of BMS SoC. After behavioral simulations, circuit and layout design and simulation, the ∑-△ modulator ENOB reaches 16. 58, and SNDR reaches 101.6 dB, which achieves design requirements. The system-level verification of high-precision acquisition front-end circuit and the design of its ∑-△ADC modulator make preparations for the implementation of high-precision acquisition front-end in BMS SoC.