The document describes the features and functions of the bq2058 Lithium Ion Pack Supervisor, including overvoltage, undervoltage, and overcurrent protection. It is designed for three to four Li-Ion series cells and can be part of a low-cost Li-Ion charge control system.
The bq2058 is designed to control charge and discharge cell voltages for lithium ion battery packs containing three or four series cells. It protects the pack by driving external FET switches to shut off charging if any individual cell exceeds an overvoltage limit (Vov) and shuts off discharging if any cell falls below an undervoltage limit (Vuv). The device also monitors for overcurrent conditions, such as short circuits.
The chip features minimal external components and operates with a low supply current of 25µA typical. It is available in a 16-pin narrow SOIC package. Overvoltage thresholds are mask-programmable by Unitrode (a Texas Instruments company), offering various options like 4.25V, 4.30V, and others depending on the specific part number.
| Supply current | 25µA typical |
|---|---|
| Sleep current | 0.7µA typical |
| Package type | 16-pin 150-mil narrow SOIC |
| Overvoltage threshold (Standard) | 4.25V |
| Sample rate | Every 40ms (typical) |
The standard version has an overvoltage limit of 4.25V.
It detects overcurrent in the discharge direction when the voltage difference across sense resistors exceeds 160mV.