TI BQ7791500PWT

The BQ77915 device is a low-power battery pack protector that implements a comprehensive set of voltage, current, and temperature protection functions, as well as an intelligent battery balancing algorithm, without the need for microcontroller (MCU) control. The stackable interface of this device allows for simple expansion, supporting battery applications from 3-series to 20 or more series-connected cells. Both the protection thresholds and delays are factory-programmed, with multiple configurations available for selection. To enhance flexibility, separate over-temperature and under-temperature discharge thresholds (OTD and UTD) and over-temperature and under-temperature charge thresholds (OTC and UTC) are provided. This device can achieve battery pack protection through the integrated independent CHG and DSG low-side NMOS FET drivers, which can be disabled via two control pins. These control pins can also provide a battery protection solution for more series-connected cells (6 cells and above) in a simple and cost-effective manner. To do this, simply cascade the CHG and DSG outputs of the upper-level device to the control pins of the lower-level device. To achieve greater flexibility, the over-current discharge protection delay can be programmed by connecting a resistor from the OCDP pin to VSS. The BQ77915 protector implements an intelligent passive battery balancing algorithm through the integrated FETs capable of achieving a battery balancing current of up to 50mA. For higher battery balancing current requirements, it can be achieved by connecting external FETs. The sleep mode, designed for battery pack transportation and storage purposes, supports ultra-low-power operation. The BQ77915 protector can be used in battery packs without host monitoring.

• Comprehensive voltage, current, and temperature protection
• Voltage protection (overvoltage accuracy ±10mV, undervoltage accuracy 10)
• Overvoltage: 3V to 4.575V, undervoltage: 1.2V to 3V
• Open-wire battery and disconnection detection (OW)
• Current protection
• Overcurrent discharge 1: -10mV to -85mV, overcurrent discharge 2: -20mV to -170mV
• Short-circuit discharge: -40mV to -340mV
• Temperature protection
• Overtemperature charging: 45°C to 50°C
• Overtemperature discharging: 65°C to 70°C
• Independent CHG and DSG FET drivers
• Smart cell balancing algorithm via integrated FET (balancing current up to 50mA), with support for higher balancing current via external FET
• Ultra-low power sleep mode
• Absolute maximum rated voltage up to 36V per cell input
• OCD1/2 delay programmable via resistor
• Shutdown mode: 0.5μA (maximum)
• Functional safety support
• Documentation to assist functional safety system design

• Power tools, garden tools
• Cleaning robots, vacuum cleaners, hoverboards
• Electric bicycles
• 10.8V to 72V battery packs