LTC6802-2 Datasheet

• Qualified for Automotive Applications
• Measures Up to 12 Li-Ion Cells in Series (60V Max)
• Stackable Architecture Enables Monitoring High Voltage Battery Stacks
• Individually Addressable with 4-Bit Address
• 0.25% Maximum Total Measurement Error
• 13ms to Measure All Cells in a System
• Cell Balancing:
  • On-Chip Passive Cell Balancing Switches
  • Provision for Off-Chip Passive Balancing
• Two Thermistor Inputs Plus Onboard Temperature Sensor
• 1MHz Serial Interface with Packet Error Checking
• High EMI Immunity
• Delta-Sigma Converter with Built-In Noise Filter
• Open-Wire Connection Fault Detection
• Low Power Modes
• 44-Lead SSOP Package

• Electric and Hybrid Electric Vehicles
• High Power Portable Equipment
• Backup Battery Systems
• High Voltage Data Acquisition Systems

The LTC6802-2 is a complete battery monitoring IC that includes a 12-bit ADC, a precision voltage reference, a high voltage input multiplexer and a serial interface. Each LTC6802-2 can measure 12 series connected battery cells, with a total input voltage up to 60V. The voltage on all 12 input channels can be measured within 13ms.

Many LTC6802-2 devices can be stacked to measure the voltage of each cell in a long battery string. Each LTC6802-2 has an individually addressable serial interface, allowing up to 16 LTC6802-2 devices to interface to one control processor and operate simultaneously.

To minimize power, the LTC6802-2 offers a measure mode to monitor each cell for overvoltage and undervoltage conditions. A standby mode is also provided to reduce supply current to 50µA.

Each cell input has an associated MOSFET switch that can discharge any overcharged cell.

The related LTC6802-1 offers a serial interface that allows the serial ports of multiple LTC6802-1 devices to be daisy chained without opto-couplers or isolators.