1 Features

• Qualified for Automotive Applications
• AEC-Q100 Qualified With the Following Results:
  • Device Temperature Grade 1: -40°C to 125°C Ambient Operating Temperature Range
  • Device HBM ESD Classification Level H2
  • Device CDM ESD Classification Level C5
• Single Cell LiFePO₄ Charging Algorithm
• 30-V Input Rating, With 10.5-V Overvoltage Protection (OVP)
• 50-mA Integrated Low Dropout Linear Regulator (LDO)
• Programmable Charge Current Through ISET and EN Terminals
• Thermal Regulation and Protection
• Soft-Start Feature to Reduce Inrush Current
• Battery NTC Monitoring
• Charging Status Indication
• 10-Pin SON (2mm x 3mm) Package with Wettable Flanks

2 Applications

• E-call for Cars
• Automotive Telematics
• Vehicle GPS Tracking
• Car Network Video Recorder
• Smart Key
• Automotive Entertainment backup battery

3 Description

The bq25071-Q1 is a highly integrated, linear, LiFePO₄ battery charger targeted at space-limited automotive applications. It accepts power from either a USB port or AC adapter and charges a single-cell LiFePO₄ battery with up to 1 A of charge current. The 30-V input rating supports low-cost unregulated adapters.

The bq25071-Q1 has a single power output that simultaneously charges the battery and powers the system. The input current is programmable from 100 mA up to 1 A using the ISET input or configurable for USB500. There is also a 4.9 V ±10% 50 mA LDO integrated into the IC for supplying low power external circuitry.

The LiFePO₄ 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 internal temperature threshold is exceeded.

1. For all available packages, see the orderable addendum at the end of the datasheet.

Application Schematic