一文詳解ADI LTC6813－1多顆電池監(jiān)測(cè)解決方案

ADI公司的LTC6813-1是可測(cè)量到多達(dá)18顆串接電池連接的監(jiān)視器，總測(cè)量誤差小于2.2mV，電池測(cè)量范圍0-5V，所有18顆電池測(cè)量時(shí)間在290μs，內(nèi)置isoSPI?接口，主要用在電動(dòng)和混合動(dòng)力汽車以及備份電池系統(tǒng)。本文介紹了LTC6813-1主要特性，框圖和多種應(yīng)用電路，以及演示板DC2350A主要性能和電路圖。

The LTCR6813-1 is a multicell battery stack monitor thatmeasures up to 18 series connected battery cells witha total measurement error of less than 2.2mV. The cell measurement range of 0V to 5V makes the LTC6813-1suitable for most battery chemistries. All 18 cells can bemeasured in 290μs， and lower data acquisition rates canbe selected for high noise reduction.

Multiple LTC6813-1 devices can be connected in series，permitting simultaneous cell monitoring of long， highvoltage battery strings. Each LTC6813-1 has an isoSPIinterface for high speed， RF immune， long distance communications.Multiple devices are connected in a daisychain with one host processor connection for all devices.

This daisy chain can be operated bidirectionally， ensuringcommunication integrity， even in the event of a fault alongthe communication path.

The LTC6813-1 can be powered directly from the batterystack or from an isolated supply. The LTC6813-1 includespassive balancing for each cell， with individual PWM dutycycle control for each cell. Other features include an onboard5V regulator， nine general purpose I/O lines and asleep mode， where current consumption is reduced to 6μA.

LTC6813-1主要特性：

nnMeasures Up to 18 Battery Cells in Series

nn2.2mV Maximum Total Measurement Error

nnStackable Architecture Supports 100s of Cells

nnBuilt-In isoSPI? Interface

nn1Mb Isolated Serial Communications

nnUses a Single Twisted Pair， Up to 100 Meters

nnLow EMI Susceptibility and Emissions

nnBidirectional for Broken Wire Protection

nn290μs to Measure All Cells in a System

nnSynchronized Voltage and Current Measurement

nn16-Bit Delta-Sigma ADC with Programmable3rd Order Noise Filter

nnEngineered for ISO 26262-Compliant Systems

nnPassive Cell Balancing Up to 200mA （Max） withProgrammable Pulse?Width Modulation

nn9 General Purpose Digital I/O or Analog Inputs

nnTemperature or Other Sensor Inputs

nnConfigurable as an I2C or SPI Master

nn6μA Sleep Mode Supply Current

nn64-Lead eLQFP Package

LTC6813-1應(yīng)用：

nnElectric and Hybrid Electric Vehicles

nnBackup Battery Systems

nnGrid Energy Storage

nnHigh Power Portable Equipment

圖1.LTC6813-1框圖

圖2.LTC6813-1變壓器隔離菊花鏈配置圖

圖3.LTC6813-1采用2線端口A的連接圖

圖4.LTC6813-1可逆isoSPI菊花鏈接圖

圖5.LTC6813-1單板菊花鏈接口元件圖

圖6.LTC6813-1同一PCB的電容隔離耦合圖

圖7.LTC6813-1 16顆和14顆電池連接圖

演示板DC2350A

Demonstration circuit 2350A is a multicell battery stackmonitor featuring the LTC?6812-1， a 15-cell monitor onthe DC2350A-A， or the LTC6813-1， an 18-cell monitor onthe DC2350A-B. Multiple boards can be linked through a2-wire isolated serial interface （isoSPI） to monitor anynumber of cells in a stack. The demo circuit also featuresreversible isoSPI enabling a fully redundant communicationpath.

The DC2350 can communicate to a PC by connectingdirectly to a DC2026 Linduino? One. The DC2026 must beloaded with the appropriate program （called a “sketch”）to control the battery stack monitor IC and receive datathrough a USB serial port. The DC2792/DC1941 can beconnected to the DC2026 to provide a fully isolated isoSPI interface to the DC2350.

演示板DC2350A主要性能：

圖8.演示板DC2350A電路圖（1）

圖9.演示板DC2350A電路圖（2）