Using the DS2786 battery fuel gauge in a 2-cell battery pack

The DS2786 stand-alone open-circuit-voltage (OCV)-based fuel gauge estimates available capacity for Li-ion and polymer batteries based on the cell voltage in an open-circuit state following a relaxation period. The 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.

While the DS2786's operating range is designed for use with a single-cell Li+ battery pack, it can also be used in a 2-cell battery pack with the addition of a few components. This application note details a circuit that only requires two additional ICs to utilize the DS2786 in a 2-cell battery pack. This circuit allows the use of all the DS2786's features, including on-chip voltage, current, and temperature measurement; two auxiliary voltage inputs; and a two-wire interface.

Please view the PDF document for more information.