describe
LTC ® 2949 is a high-precision current, voltage, temperature, charging, and energy meter used for electrical and hybrid vehicles and other isolated current sensing applications. It infers the charging and energy entering and exiting the battery pack by simultaneously monitoring up to two induction resistors and the voltage drop on the battery pack voltage.
Low offset ΔΣ ADC ensures accurate measurement of voltage and current, with significant power loss. The continuous integration of current and power ensures non-destructive tracking of the charging and energy transmitted or received by the battery pack.
The built-in serial interface can be configured to support isolated ectopic SPI communication with the host, or as an SPI interface.
The LTC2949 has 12 internally buffered high impedance inputs (V1 to V12) for measuring voltage from external sensors or resistive dividers, allowing for temperature measurement, high-voltage link voltage, chassis isolation, and monitoring of contactor status. LTC2949 has up to 5 programmable digital outputs that can be set to ground, power, or switch at 400 kHz.
Programmable thresholds and tracking registers reduce digital traffic to the host.

FEATURES

n Measures Battery Stack Voltage, Current and Power
n Indicates Accumulated Battery Charge and Energy
n 20-Bit Current Measurement with <1μV Offset
n Built-In Isolated isoSPI™ or SPI Interface
n LTC68xx/ADBMS68xx Compatible, Supports 
Synchronous Measurements with Cell Monitors
n Up to 12 Buffered Voltage Measurement Inputs
n Up to 5 GPOs, Configurable to Drive Ground, Supply 
or Toggling at 400kHz
n High or Low Side Current Sense
n 0.3% Current and Voltage Accuracy
n 1% Energy and Charge Accuracy
n True Average ADCs
n I
2C EEPROM Interface to Store Board Calibration Factors
n Threshold Registers for all Measured Quantities
n Engineered for ISO26262 Compliant Systems
n Open Wire Detection on Input Pins
n Available in 48-Lead LQFP Package
n AEC-Q100 Qualified for Automotive Applications
APPLICATIONS
n Electric and Hybrid Vehicles
n Isolated Current Sensing
n Backup Battery Systems

n High Power Portable Equipment