Lithium-Ion protector chip

Maxim introduces the DS2726, a stand-alone protection IC with integrated cell balancing for 5- to 10-cell lithium-ion (Li+) battery packs. The solution combines voltage and current monitoring with cell balancing in a single chip, the DS2726 provides a solution for battery-operated devices. It is thus an protector for power tools, e-bikes, portable household appliances, battery-backup systems, or any application with a 5- to 10-cell Li+ battery pack. The DS2726 employs high-side p-channel protection FETs to provide overvoltage, undervoltage, discharge-current, and short-circuit protection. The protection circuit monitors individual cell voltages to detect overvoltage and undervoltage conditions. Additionally, high-side protection allows the host system to maintain communication with a fuel gauge, such as the DS2788, even when a fault condition causes the protection FETs to switch off.

The DS2726 eliminates the need for an external microcontroller to configure the device. Voltage-protection and cell-balancing thresholds are pin programmable; overdischarge and short-circuit current limits are set with external resistors; and overdischarge and short-circuit current time-out delays are set with external capacitors. This device thus provides robust protection while extending battery life by ensuring that all cells are equally charged. During cell balancing, internal switches shunt an industry-leading 150mA (typ) of current. For added flexibility, cell balancing can be enabled automatically on detection of a charger or by signaling a control pin. The DS2726 is available in a space-saving, 7mm x 7mm, 32-pin TQFN package. Prices start at $4.58 (1000-up, FOB USA). Samples and evaluation kits are available.