DESCRIPTION

The LTC?6811 is a multicell battery stack monitor that

measures up to 12 series connected battery cells with

a total measurement error of less than 1.2mV. The cell

measurement range of 0V to 5V makes the LTC6811

suitable for most battery chemistries. All 12 cells can be

measured in 290μs, and lower data acquisition rates can

be selected for high noise reduction.

Multiple LTC6811 devices can be connected in series, permitting

simultaneous cell monitoring of long, high voltage

battery strings. Each LTC6811 has an isoSPI interface for

high speed, RF-immune, long distance communications.

Using the LTC6811-1, multiple devices are connected in

a daisy chain with one host processor connection for all

devices. Using the LTC6811-2, multiple devices are connected

in parallel to the host processor, with each device

individually addressed.

The LTC6811 can be powered directly from the battery

stack or from an isolated supply. The LTC6811 includes

passive balancing for each cell, with individual PWM

duty cycle control for each cell. Other features include an

onboard 5V regulator, five general purpose I/O lines and a

sleep mode, where current consumption is reduced to 4μA.

FEATURES

- Pin-Compatible Upgrade from the LTC6804

- Measures Up to 12 Battery Cells in Series

- 1.2mV Maximum Total Measurement Error

- Stackable Architecture for High Voltage Systems

- Built-in isoSPITM Interface

- 1Mb Isolated Serial Communications

- Uses a Single Twisted Pair, up to 100 Meters

- Low EMI Susceptibility and Emissions

- 290μs to Measure All Cells in a System

- Synchronized Voltage and Current Measurement

- 16-Bit ADC with Programmable Noise Filter

- Engineered for ISO 26262-Compliant Systems

- Passive Cell Balancing with Programmable Timer

- 5 General Purpose Digital I/O or Analog Inputs

- Temperature or other Sensor Inputs

- Configurable as an I2C or SPI master

- 4μA Sleep Mode Supply Current

- 48-Lead SSOP Package

- AEC-Q100 Qualified for Automotive Applications

APPLICATIONS

- Electric and Hybrid Electric Vehicles

- Backup Battery Systems

- Grid Energy Storage

- High Power Portable Equipment