Texas Instruments' 3 series to 20 series stack protection function, independent battery balance and sleep mode

     The Texas Instruments BQ77915 is a low-power battery pack protector with voltage, current and temperature protection and does not require a microcontroller (MCU) controlled smart battery balancing algorithm. The device's stacking interface provides simple scaling to support battery cell applications from Series 3 to Series 20 or more. Protection thresholds and delays are factory programmed and available in a variety of configurations. For added flexibility, separate thresholds for overtemperature discharge (OTD), undertemperature discharge (UTD), overtemperature charge (OTC), and undertemperature charge (UTC) are provided.

     The device is packaged with an integrated independent charge (CHG) and discharge (DSG) low-side NMOS FET driver that can be disabled with two control pins. These control pins provide battery protection solutions for higher series (Series 6 and up) in a simple and economical manner. To do this, cascade a higher device CHG and DSG output directly to the lower device control pin. The discharge overcurrent protection delay provides flexibility and can be programmed using a resistor connected from the OCDP pin to the V(SS).

     BQ77915 protector realizes intelligent passive battery balancing algorithm by integrating FETs, and the battery balance current can reach up to 50 mA. For higher cell balance current requirements, an external field effect tube can be connected. HIBERNATE patterns for shipping and storage support ultra-low power operations. The BQ77915 protector is designed for battery packs and no host monitoring is required.