L6924UTR datasheet(4/37 Pages) STMICROELECTRONICS

4 / 37 page

Description

L6924U

4/37

Doc ID 14716 Rev 2

Description

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

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

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

from an AC wall adapter. The ideal solution for space-limited portable products 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 monitors and protects the battery from unsafe

thermal conditions.

Figure 2.

Basic application schematic

Figure 1.

Minimum size application board

L6924UTR 数据表(PDF) 4 Page - STMicroelectronics