LTC6813-1 Datasheet

• AEC-Q100 Qualified for Automotive Applications
• Measures Up to 18 Battery Cells in Series
• 2.2mV Maximum Total Measurement Error
• Stackable Architecture for High Voltage Systems
• Built-In isoSPI^™ Interface
  • 1Mb Isolated Serial Communications
  • Uses a Single Twisted Pair, Up to 100 Meters
  • Low EMI Susceptibility and Emissions
  • Bidirectional for Broken Wire Protection
• 290µs 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 Inputs
  • 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

• Electric and Hybrid Electric Vehicles
• Backup Battery Systems
• Grid Energy Storage
• High Power Portable Equipment

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

Multiple LTC6813-1 devices can be connected in series, permitting simultaneous cell monitoring of long, high voltage battery strings. Each LTC6813-1 has an isoSPI 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 LTC6813-1 can be powered directly from the battery stack or from an isolated supply. The LTC6813-1 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.