The UNDERVOLTAGE mode is detected if any of the cell voltage across (V1–VSS), (V2–V1), (V3–V2), or (V4–V3) is below the V_UVREG threshold for t_{UV_DELAY} time. In this mode, the regulated output is disabled. To return to the NORMAL mode, all the cell voltages must be above (V_UVREG + V_UVHYS).

For a low cell configuration, V_n pin can be shorted to the (V_{n – 1}) pin. The device ignores any differential cell voltage below V_UVQUAL threshold for undervoltage detection.