bq77905, Low-Power Battery Protector

TI offers its bq77905, 3- to 5-series, Li-Ion and Li-phosphate, ultra-low-power, stackable battery protector

Image of Texas Instruments' bq77905 Low-Power Battery ProtectorTexas Instruments' bq77905 device is a low-power battery pack protector that implements a suite of voltage, current, and temperature protections without microcontroller (MCU) control. Protection thresholds and delays are factory-programmed and available in a variety of configurations. Separate over-temperature and under-temperature thresholds for discharge (OTD and UTD) and charge (OTC and UTC) are provided for added flexibility.

The device achieves pack protection via the integrated, independent CHG and DSG, low-side NMOS FET drivers, which may be disabled via two control pins. These control pins may also be used to achieve cell-protection solutions for higher series (6S and beyond) in a simple and economical manner. To do this, simply cascade a higher device's CHG and DSG outputs to the immediate lower device's control pins. For reduced component count, all protection faults use internal delay timers.

  • Voltage protection (accuracy ±10 mV)
    • Over-voltage: 3 V to 4.575 V
    • Under-voltage: 1.2 V to 3 V
  • Open-cell and open-wire detection (OW)
  • Current protection
    • Over-current discharge 1: -10 mV to -85 mV
    • Over-current discharge 2: -20 mV to 170 mV
    • Short-circuit discharge: -40 mV to 340 mV
    • Accuracy ±20% for ≤ 20 mV, ±30% for > 20 mV across full temperature
  • Normal mode: 6 µA
  • Shutdown mode: 0.5 µA (max.)
  • Temperature protection
    • Over-temperature charge: 45°C or 50°C
    • Over-temperature discharge: 65°C or 70°C
    • Under-temperature charge: -5°C or 0°C
    • Under-temperature discharge: -20°C or -10°C
  • Additional features
    • Independent charge (CHG) and discharge (DSG) FET drivers
    • SimpleStack interface for easy stacking
    • 36 V absolute maximum rating per cell input
    • Built-in, self-test functions for high reliability

bq77905, Low-Power Battery Protector

ImageManufacturer Part NumberDescriptionFunctionBattery ChemistryNumber of CellsAvailable QuantityView Details
BQ7790500PW datasheet linkIC LITHIUM BATT PROTECT 20TSSOPBQ7790500PWIC LITHIUM BATT PROTECT 20TSSOPBattery ProtectionLithium-Ion3 ~ 586 - Immediate
BQ7790500PW product page link

Evaluation Board

ImageManufacturer Part NumberDescriptionAvailable QuantityView Details
BQ77905EVM-707 datasheet linkEVAL BOARD FOR BQ77905BQ77905EVM-707EVAL BOARD FOR BQ779058 - Immediate
101 - Factory Stock
BQ77905EVM-707 product page link
Published: 2016-10-05