LTC6804-1/LTC6804-2 Multicell Battery Monitors Fea T Descrip T n Measures Up to 12 Battery Cells in Series The LTC 6804 is a 3rd generation multicell battery stack n Stackable Architecture Supports 100s of Cells monitor that measures up to 12 series connected battery n Built-In isoSPI Interface: cells with a total measurement error of less than 1.2mV. The 1Mbps Isolated Serial Communications cell measurement range of 0V to 5V makes the LTC6804 Uses a Single Twisted Pair, Up to 100 Meters suitable for most battery chemistries. All 12 cell voltages Low EMI Susceptibility and Emissions can be captured in 290s, and lower data acquisition rates n 1.2mV Maximum Total Measurement Error can be selected for high noise reduction. n 290s to Measure All Cells in a System Multiple LTC6804 devices can be connected in series, n Synchronized Voltage and Current Measurement permitting simultaneous cell monitoring of long, high volt- n 16-Bit Delta-Sigma ADC with Frequency Program- age battery strings. Each LTC6804 has an isoSPI interface mable 3rd Order Noise Filter for high speed, RF-immune, local area communications. n Engineered for ISO26262 Compliant Systems Using the LTC6804-1, multiple devices are connected in n Passive Cell Balancing with Programmable Timer a daisy-chain with one host processor connection for all n 5 General Purpose Digital I/O or Analog Inputs: devices. Using the LTC6804-2, multiple devices are con- Temperature or other Sensor Inputs nected in parallel to the host processor, with each device 2 Configurable as an I C or SPI Master individually addressed. n 4A Sleep Mode Supply Current n Additional features include passive balancing for each cell, 48-Lead SSOP Package an onboard 5V regulator, and 5 general purpose I/O lines. a T In sleep mode, current consumption is reduced to 4A. The LTC6804 can be powered directly from the battery, n Electric and Hybrid Electric Vehicles or from an isolated supply. n Backup Battery Systems L, LT, LTC, LTM, Linear Technology and the Linear logo are registered and isoSPI is a n Grid Energy Storage trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. patents, including 8908799, 9182428, 9270133. n High Power Portable Equipment Typical a T IPB Total Measurement Error + LTC6804-1 vs Temperature of 5 Typical Units IMB 12S1P 2.0 ILP IPA CELL VOLTAGE = 3.3V + 5 TYPICAL UNITS 1.5 IMA 1.0 0.5 IPB + 0 LTC6804-1 IMB 0.5 IPA + 1.0 1.5 IMA 2.0 MPU 50 25 0 25 50 75 100 125 IPB + TEMPERATURE (C) LTC6804-1 680412 TA01b SPI IMB IPA IP + LTC6820 IMA IM 680412 TA01a 680412fc 1 For more information www.linear.com/LTC6804-1 MEASUREMENT ERROR (mV) ion pplica ions pplica ion uresLTC6804-1/LTC6804-2 Table o F c T Ts Features ..................................................... 1 Data Link Layer .......................................................44 Applications ................................................ 1 Network Layer ........................................................44 Typical Application ........................................ 1 Programming Examples .........................................54 Description.................................................. 1 Simple Linear Regulator .........................................58 Absolute Maximum Ratings .............................. 3 Improved Regulator Power Efficiency .....................58 Pin Configuration .......................................... 3 Fully Isolated Power ................................................59 Order Information .......................................... 4 Reading External Temperature Probes ....................59 Electrical Characteristics ................................. 4 Expanding the Number of Auxiliary Pin Functions .............................................. 17 Measurements ........................................................60 Block Diagram ............................................. 18 Internal Protection Features ....................................60 Operation................................................... 20 Filtering of Cell and GPIO Inputs .............................60 State Diagram .........................................................20 Cell Balancing with Internal Mosfets .......................62 LTC6804 Core State Descriptions ...........................20 Cell Balancing with External MOSFETS...................62 isoSPI State Descriptions .......................................21 Discharge Control During Cell Measurements ........62 Power Consumption ...............................................21 Power Dissipation and Thermal Shutdown .............63 ADC Operation ........................................................21 Method to Verify Balancing Circuitry ......................63 Data Acquisition System Diagnostics .....................26 Current Measurement with a Hall Effect Sensor .....66 Watchdog and Software Discharge Timer ..............30 Current Measurement with a Shunt Resistor ..........66 2 I C/SPI Master on LTC6804 Using GPIOS ..............31 Using the LTC6804 with Less Than 12 Cells ...........67 Serial Interface Overview ........................................35 Package Description ..................................... 76 4-Wire Serial Peripheral Interface (SPI) Revision History .......................................... 77 Physical Layer ........................................................36 Typical Application ....................................... 78 2-Wire Isolated Interface (isoSPI) Physical Layer ...36 Related Parts .............................................. 78 680412fc 2 For more information www.linear.com/LTC6804-1 en on