• Small 3,5 mm × 4,5 mm QFN Package
• Designed for Single-Cell Li-Ion- or Li-Polymer-Based Portable Applications
• Integrated Dynamic Power-Path Management (DPPM) Feature Allowing the AC Adapter to Simultaneously Power the System and Charge the Battery
• Power Supplement Mode Allows Battery to Supplement the AC Input Current
• Autonomous Power Source Selection (AC Adapter or BAT)
• Supports Up to 2 Amps Total Current
• Thermal Regulation for Charge Control
• Charge Status Outputs for LED or System Interface Indicates Charge and Fault Conditions
• Reverse Current, Short-Circuit, and Thermal Protection
• Power Good Status Outputs
• 4.4-V and 6-V Options for System Output Regulation Voltage
• APPLICATIONS
  • Smart Phones and PDA
  • MP3 Players
  • Digital Cameras and Handheld Devices
  • Internet Appliances

The bq24070 and bq24071 are highly integrated Li-ion linear charger and system power-path management devices targeted at space-limited portable applications. The bq24070/1 offer DC supply (AC adapter) power-path management with autonomous power-source selection, power FETs and current sensors, high-accuracy current and voltage regulation, charge status, and charge termination, in a single monolithic device.

The bq24070/1 power the system while independently charging the battery. This feature reduces the charge and discharge cycles on the battery, allows for proper charge termination and allows the system to run with an absent or defective battery pack. This feature also allows for the system to instantaneously turn on from an external power source in the case of a deeply discharged battery pack. The IC design is focused on supplying continuous power to the system when available from the AC adapter or battery sources.

The MODE pin selects the priority of the input sources. If an input source is not available, then the battery is selected as the source. With the MODE pin high, the bq24070/1 attempts to charge from the input at the charge rate set by ISET1 pin. With the MODE pin low, the bq24070/1 defaults to USB charging at the charge rate. This feature allows the use of a single connector (mini-USB cable), where the host programs the MODE pin according to the source that is connected (AC adaptor or USB port). summarizes the MODE pin function.