bq2058

The bq2058 Lithium Ion Pack Supervisor is designed to control the charge and discharge cell voltages for three or four lithium ion (Li-Ion) series cells, accommodating battery packs containing series/parallel configurations. The low operating current does not overdischarge the cells during periods of storage and does not significantly increase the system discharge load. The bq2058 can be part of a low-cost Li-Ion charge control system within the bat-terypack.


The bq2058 controls two external FETs to limit the charge and discharge potentials. The bq2058 allows charging when each individual cell voltage is below VOV (overvoltage limit). If the voltage on any cell exceeds VOV for a user-configurable delay period (tOVD), the CHG pin is driven high, shutting off charge to the battery pack. This safety feature pre-vents overcharge of any cell within the battery pack. After an overvoltage condition occurs, each cell must fall below VCE (charge enable voltage) forthebq2058tore-enablecharging.


The bq2058 protects batteries from overdischarge. If the voltage on any cell falls below VUV (undervoltage limit) for a user-configurable delay pe-riod (t ), the DSG output is driven UVD high, shutting off the battery discharge. This safety feature prevents overdischarge of any cell within the batterypack.


The bq2058 also stops discharge on detection of an overcurrent condition, such as a short circuit. If an overcurrent condition occurs for a user-configurable delay period (tOCD), the DSG output is driven high,disconnecting the load from the pack. DSG remains high until removal of the short circuitorovercurrentcondition.