A multi-cell battery pack monitoring chip based on 0.35-μm BCD technology for electric vehicles

作者:Wang, Xiaofei*; Zhang, Hong; Zhang, Jianrong; Li, Changyi; Du, Xin; Hao, Yue
来源:IEICE Electronics Express, 2015, 12(12): 20150367.
DOI:10.1587/elex.12.20150367

摘要

This letter presents a multi-cell battery pack monitoring chip for electric vehicles (EVs). A multiplexer based on p- and n-type lateral double-diffused MOS (LDMOS) transistors is proposed to select the battery voltage in a battery pack with up to 12 series-connected battery cells. Measuring of the cell voltages is realized by a 12-bit incremental Sigma Delta analog-to-digital converter (ADC) with offset cancellation. Fabricated in a 0.35-mu m Bipolar-CMOS-DMOS (BCD) technology, measurement results show that an absolute conversion error of less than 3 mV is obtained. The conversion time for each cell is less than 600 mu s under a 1-MHz clock signal generated by an internal oscillator. The chip area is 4 x 3.8 mm(2) and the current consumption is 510 mu A in measuring mode, resulting in a operation power loss of 25.5 mW under a 50-V power supply.