LTC6803-3 Datasheet

• Measures Up to 12 Battery Cells in Series
• Stackable Architecture
• Supports Multiple Battery Chemistries and Supercapacitors
• Serial Interface Daisy Chains to Adjacent Devices
• 0.25% Maximum Total Measurement Error
• Engineered for ISO26262 Compliant Systems
• 13ms to Measure All Cells in a System
• Passive Cell Balancing:
  • Integrated Cell Balancing MOSFETs
  • Ability to Drive External Balancing MOSFETs
• On-board Temperature Sensor and Thermistor Inputs
• 1MHz Serial Interface with Packet Error Checking
• Safe with Random Connection of Cells
• Built-In Self Tests
• Delta-Sigma Converter With Built-In Noise Filter
• Open-Wire Connection Fault Detection
• 12μA Standby Mode Supply Current
• High EMI Immunity
• 44-Lead SSOP Package

• Electric and Hybrid Electric Vehicles
• High Power Portable Equipment
• Backup Battery Systems
• Electric Bicycles, Motorcycles, Scooters

The LTC6803 is a 2nd generation, complete battery monitoring IC that includes a 12-bit ADC, a precision voltage reference, a high voltage input multiplexer and a serial interface. Each LTC6803 can measure up to 12 series-connected battery cells or supercapacitors. Using a unique level shifting serial interface, multiple LTC6803-3 devices can be connected in series, without opto-couplers or isolators, allowing for monitoring of every cell in a long string of series-connected batteries. Each cell input has an associated MOSFET switch for discharging overcharged cells. It is pin compatible with the LTC6802-1, providing a drop-in upgrade. The LTC6803-3 separates the bottom of the stack from V^–, improving cell 1 measurement accuracy.

The LTC6803 provides a standby mode to reduce supply current to 12μA. Furthermore, the LTC6803 can be powered from an isolated supply, providing a technique to reduce battery stack current draw to zero.

For applications requiring individually addressable serial communications, see the LTC6803-2/LTC6803-4.