Ultra-low-power battery pack protectors has suite of protection features

Texas Instruments BQ77915 Ultra-Low-Power Battery Pack Protectors employs a suite of voltage, current, and temperature protection features. The device uses a smart cell balancing algorithm without the use of an MCU. The protector is intended for battery packs where no host monitoring is required. The device uses a stackable interface that offers simple scaling which supports battery cell applications from three to 20 series and beyond. Factory-programmed protection thresholds and delays are supplied in a wide range of configurations. Separate overtemperature and undertemperature thresholds provide added flexibility for both charge (OTC and UTC) and discharge (OTD and UTD). Pack protection on the device is supported via the integrated independent CHG and DSG low-side NMOS FET drivers. These drivers may be disabled through two control pins. These pins also can be used to achieve cell protection solutions for higher series in an easy and economical manner. These solutions are achieved by simply cascading a higher device CHG and DSG outputs to the immediate lower device control pins. Discharge overcurrent protection delays can be programmed using a resistor connected from the OCDP pin to VSS thus adding adaptability. The protector achieves a smart passive cell-balancing algorithm by using integrated FETs for cell balancing currents up to 50mA.