L6924U datasheet(4/38 Pages) STMICROELECTRONICS

4 / 38 page

Device description

L6924U

4/38

Device description

The L6924U is a fully monolithic battery charger that safely charges single-cell

Li-Ion/Polymer battery from either USB power source or AC adapter. In USB mode, the

L6924U supports both low power and high power mode. Alternatively the device can charge

from AC wall adapter.

The ideal solution for space-limited portable products is produced in BCD6 technology and

integrates the power MOSFET, reverse blocking diode, sense resistor and thermal

protection into a compact VFQFPN16 package. When an external voltage regulated adapter

or USB port is used, the L6924U works in linear mode, and charges the battery in a

constant current constant voltage (CC/CV) profile. Moreover, when a current-limited adapter

is used, the device can operate in quasi-pulse mode, dramatically reducing the power

dissipation. Regardless of the charging approach, a closed loop thermal control avoids

device overheating. The device has an operating input voltage ranging from 2.5 V to 12 V

and it allows the user to program many parameters, such as fast-charge current, end-of-

charge current threshold, and charge timer. The L6924U offers two open collector outputs

for diagnostic purposes, which can be used to either drive two external LEDs or

communicate with a host microcontroller. Finally, the L6924U also provides other features

like gas gauge function, check for battery presence, and monitoring and protecting the

battery from unsafe thermal conditions.

Figure 2.

Basis application schematic

Figure 1.

Minimum size application board

L6924U Datasheet(PDF) 4 Page - STMicroelectronics