bq25071 Datasheet | Texas Instruments

Product Folder Sample & Buy Technical Documents Tools & Software Support & munity bq25071 SLUSBK6 - JULY 2014 bq25071 1-A, Single-Input, Single-Cell Li Fe PO4 Linear Battery Charger with 50 m A LDO 1 Features - 1 Single Cell Li Fe PO4 Charging Algorithm - 30V Input Rating, With 10.5 V Overvoltage Protection (OVP) - 50m A Integrated Low Dropout Linear Regulator (LDO) - Programmable Charge Current Through ISET and EN Terminals - 7% Charge Current Regulation Accuracy - Thermal Regulation and Protection - Soft-Start Feature to Reduce Inrush Current - Battery NTC Monitoring - Charging Status Indication 2 Applications - Smart Phones - Mobile Phones - Portable Media Players - Low Power Handheld Devices 3 Description The bq25071 is a highly integrated, linear, Li Fe PO4 battery charger targeted at space-limited portable applications. It accepts power from either a USB port or AC adapter and charges a single-cell Li Fe PO4 battery with up to 1 A of charge current. The 30 V input rating with 10.5 V input overvoltage protection supports low-cost unregulated adapters. The bq25071 has a single power output that simultaneously charges the battery and powers the system. The input current is programmable from 100 m A up to 1 A using the ISET input or configurable for USB500. There is also a 4.9 V ±10% 50 m A LDO integrated into the IC for supplying low power external circuitry. The Li Fe PO4 charging algorithm removes the current taper typically seen as part of the constant voltage mode control used in Li-Ion battery charge cycles which reduces charge time significantly. Instead, the battery is fast charged to the overcharge voltage and then allowed to relax to a lower float charge voltage threshold. The charger integrates the power stage with the charge current and voltage sense to achieve a high level of accuracy in the current and voltage regulation loops. An internal control loop monitors the IC junction temperature through the charge cycle and reduces the charge current if an...