The bq2461x is highly integrated Li-ion or Li-polymer switch-mode battery charge controllers. The bq2463x is highly integrated switch-mode battery charge controllers designed specifically to charge Lithium Phosphate battery chemistries. They offer a constant-frequency synchronous PWM controller with high accuracy charge current and voltage regulation, adapter current regulation, termination, charge preconditioning, and charge status monitoring, The bq2461x/bq2463x charges the battery in three phases: preconditioning, constant current, and onstant voltage. Charge is terminated when the current reches a minimum user-selectable level. A programmable charge timer provides a safety backup for charge termination. The q2461x/bq2463x automatically restarts the charge cycle if the battery voltage falls below an internal threshold, and enters a low-quiescent current sleep mode when the input voltage falls below the battery voltage.