The DS2786G+T&R is a stand-alone OCV based fuel gauge in 10 pin TDFN package. This device estimates available capacity for rechargeable Li-ion (Li+) and Li+ polymer batteries based on the cell voltage in the open-circuit state following a relaxation period. The open-circuit voltage (OCV) is used to determine relative cell capacity based on a lookup table stored in the IC. This capability makes accurate capacity information available immediately after a battery pack is inserted. The DS2786B uses coulomb counting as a secondary means of estimating relative capacity, remaining capacity is reported in percent along with cell voltage, current and temperature information. Cell characteristics and calculations are stored in on-chip EEPROM. Temperature data is available from an on-die sensor, resistance measurements of a pack identification resistor and pack thermistor are supported by ratiometric measurements on two auxiliary inputs.
● Supply voltage range is 2.5V to 4.5V
● Operating temperature range from -20°C to 70°C
● Measurement and estimated capacity data are accessed through an I2C interface
● Relative capacity calculated from coulomb counter and open-circuit cell voltage (OCV) battery model
● Accurate warning on low battery conditions, low power consumption
● 12bit battery voltage measurement with ±10mV accuracy, 1.22mV LSB (0V to 4.5V) input range
● 11bit bidirectional current measurement with 25µV LSB ±51.2mV dynamic range, 1.67mA LSB at ±3.4A
● Current accumulation measurement resolution ±204.8mVh and ±13.65Ah (RSNS = 15mohm) range
● Internal temperature measurement of 0.125°C LSB, ±3°C accuracy
