L6924D

L6924D Battery charger system with integrated power switch for Li-Ion/Li-Polymer Features Fully integrated solution, with a power MOSFET, reverse blocking diode, sense resistor, and thermal protection Ideal for coke and graphite anode single-cell L - I I packs ON Both linear and quasi-pulse operation Closed loop thermal control VFQFPN16 USB BUS-compatible Programmable charge current up to 1 A Programmable pre-charge current Programmable end-of-charge current Programmable pre-charge voltage threshold Programmable charge timer Programmable output voltage at 4.1 V and 4.2 V, with 1 % output voltage accuracy (NTC) or (PTC) thermistor interface for battery temperature monitoring and protection Flexible charge process termination Status outputs to drive LEDs or to interface with a host processor Small VFQFPN 16-leads package (3 x 3 mm) Applications PDAs Handheld devices Cellular phones Digital cameras Standalone chargers USB-powered chargers Table 1. Device summary Order code Package Packaging L6924D Tube VFQFPN16 L6924D013TR Tape and reel September 2010 Doc ID 11908 Rev 9 1/38 www.st.com 38Contents L6924D Contents 1 Description . 3 2 Pins description and connection diagrams 4 2.1 Pin description 4 3 Maximum ratings 6 3.1 Absolute maximum ratings . 6 3.2 Thermal data . 6 4 Electrical specifications 7 4.1 Electrical characteristics . 7 5 Block diagram 9 6 Operation description . 10 6.1 Linear mode . 11 6.2 Quasi-pulse mode 13 7 Applications information: charging process 16 7.1 Charging process flow chart . 16 7.2 Pre-charge current 17 7.3 Pre-charge voltage 17 7.4 Fast charge current . 18 7.5 End-of-charge current . 19 7.6 Recharge flow chart . 20 7.7 Recharge threshold . 20 7.8 Maximum charging time 20 7.9 Termination modes 22 8 Application information: monitoring and protection 23 8.1 NTC thermistor . 23 8.2 Battery absence detection 27 8.3 Status pins 27 2/38 Doc ID 11908 Rev 9