LTC6812-1 Series
15-Cell Battery Stack Monitor with Daisy Chain Interface
Manufacturer: Analog Devices
Catalog
15-Cell Battery Stack Monitor with Daisy Chain Interface
Key Features
• Measures Up to 15 Battery Cells in Series
• 2.2mV Maximum Total Measurement Error
• Stackable Architecture for High Voltage Systems
• Built-In isoSPI™Interface1Mb Isolated Serial CommunicationsUses a Single Twisted Pair, Up to 100 MetersLow EMI Susceptibility and EmissionsBidirectional for Broken Wire Protection
• 1Mb Isolated Serial Communications
• Uses a Single Twisted Pair, Up to 100 Meters
• Low EMI Susceptibility and Emissions
• Bidirectional for Broken Wire Protection
• 245μs to Measure All Cells in a System
• Synchronized Voltage and Current Measurement
• 16-Bit Delta-Sigma ADC with Programmable 3rd Order Noise Filter
• Engineered for ISO 26262-Compliant Systems
• Passive Cell Balancing Up to 200mA (Max) with Programmable Pulse-Width Modulation
• 9 General Purpose Digital I/O or Analog InputsTemperature or Other Sensor InputsConfigurable as an I2C or SPI Master
• Temperature or Other Sensor Inputs
• Configurable as an I2C or SPI Master
• 6μA Sleep Mode Supply Current
• 64-Lead eLQFP Package
• AEC-Q100 Qualified for Automotive Applications
Description
AI
The LTC6812-1 is a multicell battery stack monitor that measures up to 15 series connected battery cells with a total measurement error of less than 2.2mV. The cell measurement range of 0V to 5V makes the LTC6812-1 suitable for most battery chemistries. All 15 cells can be measured in 245μs, and lower data acquisition rates can be selected for high noise reduction.Multiple LTC6812-1 devices can be connected in series, permitting simultaneous cell monitoring of long, high voltage battery strings. Each LTC6812-1 has anisoSPI interface for high speed, RF immune, long distance communications. Multiple devices are connected in a daisy chain with one host processor connection for all devices. This daisy chain can be operated bidirectionally, ensuring communication integrity, even in the event of a fault along the communication path.The LTC6812-1 can be powered directly from the battery stack or from an isolated supply. The LTC6812-1 includes passive balancing for each cell, with individual PWM duty cycle control for each cell. Other features include an onboard 5V regulator, nine general purpose I/O lines and a sleep mode, where current consumption is reduced to 6μA.ApplicationsElectric and Hybrid Electric VehiclesBackup Battery SystemsGrid Energy StorageHigh Power Portable Equipment