ADIAD7280A1锂离子电池监测系统解决方案.docx

ADI AD7280A1锂离子电池监测系统解决方案关键词：电源管理,电池监测,锂离子电池ADI 公司AD7280A1是12位ADC,包括了监测锂离子电池组监测系统所有功能,主要用混合动力汽车,备份电池和电动工具等.AD7280A1具有内部3 ppm/的基准电压,电池电压精度1.6 mV,器件工作电压8V-30V.本文介绍AD7280A1主要特性,方框图,六个电池的配置框图和菊花链配置图,以及AD7280A锂离子电池监测系统评估板方框图,电路图,材料清单和PCB元件配置图.The AD7280A1 contains all the functions required for general- purpose monitoring of stacked lithium ion batteries as used in hybrid electric vehicles, battery backup applications, and power tools. The part has multiplexed cell voltage and auxiliary ADC measurement channels for up to six cells of battery management. An internal 3 ppm/ reference is provided that allows a cell voltage accuracy of 1.6 mV. The ADC resolution is 12 bits and allows conversion of up to 48 cells within 7 s. The AD7280A operates from a single VDD supply that has a range of 8 V to 30 V (with an absolute maximum rating of 33 V). The part provides six differential analog input channels to accommodate large common-mode signals across the full VDD range. Each channel allows an input signal range, VIN(+) VIN(), of 1 V to 5 V. The input pins assume a series stack of six cells. In addition, the part includes six auxiliary ADC input channels that can be used for temperature measurement or system diagnostics. The AD7280A includes on-chip registers that allow a sequence of channel measurements to be programmed to suit the application requirements.The AD7280A also includes a dynamic alert function that can detect whether the cell voltages or auxiliary ADC inputs exceed an upper or lower limit defined by the user. The AD7280A has cell balancing interface outputs designed to control external FET transistors to allow discharging of individual cells. The AD7280A includes a built-in self-test feature that internally applies a known voltage to the ADC inputs. A daisy-chain interface allows up to eight parts to be stacked without the need for individual device isolation. The AD7280A requires only one supply pin that accepts 6.9 mA under normal operation while converting at 1 MSPS. All this functionality is provided in a 48-lead LQFP package operating over a temperature range of 0 to +105.AD7280A1主要特性:12-bit ADC, 1 s per channel conversion time6 analog input channels, common-mode range 0.5 V to 27.5 V6 auxiliary ADC inputs1.6 mV cell voltage accuracyOn-chip voltage regulatorCell balancing interfaceDaisy-chain interfaceInternal reference: 3 ppm/oC 1.8 A power-down currentHigh input impedanceSerial interface with alert function1 SPI interface for up to 48 channelsCRC protection on read and write commandsOn-chip registers for channel sequencingVDD operating range: 8 V to 30 VTemperature range: 0 to +10548-lead LQFPQualified for automotive applicationsAD7280A1应用:Lithium ion battery monitoringElectric and hybrid electric vehiclesPower supply backupPower tools图1.AD7280A1方框图图2.AD7280A1六个电池的配置框图图3.AD7280A1菊花链配置图图4.AD7280A1电池平衡配置图AD7280A锂离子电池监测系统评估板Lithium Ion Battery Stack Monitor with Both Signal and Power Isolation(CN0197Lithium ion (Li-Ion) battery stacks contain a large number of individual cells that must be monitored correctly in order to enhance the battery efficiency and prolong the battery life. The 6-channel AD7280A devices in the circuit shown in Figure 1 act as the primary monitor providing accurate measurement data to the Battery Management Controller (BMC).The AD7280A contains an internal 3 ppm reference that allows a cell voltage measurement accuracy of 1.6 mV. The ADC resolution is 12 bits and allows conversion of up to 48 cells within 7 s.The AD7280A, which resides on the high voltage side of the Battery Management System (BMS) has a daisy-chain interface, which allows up to eight AD7280As to be stacked together and allows for 48 Li-Ion cell voltages to be monitored. Adjacent AD7280As in the stack can communicate directly, passing data up and down the stack without the need for isolation. The AD7280A master device on the bottom of the stack uses the SPI interface to communicate with the BMC, and it is only at this point that high voltage galvanic isolation is required in order to protect the low-voltage side of the BMS. The ADuM1201 digital isolator and the ADuM5401 isolator with integrated dc-to-dc converter combine to provide the required six channels of isolation in a compact and cost effective solution.This user guide describes the evaluation board kit for the AD7280A (EVAL-AD7280AEDZ), which is a complete, 12-bit resolution lithium ion battery monitoring system, integrating multiple voltage and temperature input channels. Full details about the part are available in the AD7280A data sheet from Analog Devices, Inc., which should be consulted in conjunction with this user guide when using the evaluation board.On-board components include the ADG3308 and ADG3301 bidirectional logic level translators, the ADG849 switch and the ADuM1201, and the ADuM5401 digital isolators.AD7280A锂离子电池监测系统主要特性:Full-featured evaluation board for the AD7280AEVAL-CED1Z compatibleStandalone capabilityVarious linking optionsDaisy chain capabilityPC software for control and data analysis when used with the EVAL-CED1