Device description

L6924D

4/38

1

Device description

The L6924D is a fully monolithic battery charger dedicated to single-cell Li-Ion/Polymer battery

packs. It is the ideal solution for space-limited applications, like PDAs, handheld equipment,

cellular phones, and digital cameras. It is designed with BCD6 technology and integrates all of

the power elements (the Power MOSFET, reverse blocking diode and the sense resistor) in a

small VFQFPN16 3mm x 3mm package. When an external voltage regulated wall adapter is

used, the L6924D 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 2.5V to 12V. The L6924D

allows the user to

program many parameters, such as pre-charge current, fast-charge current, pre-charge voltage

threshold, end-of-charge current threshold, and charge timer. The L6924D 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 L6924D also provides very flexible

control of the charge process termination and Gas Gauge capability, as well as other functions,

such as checking for battery presence, and monitoring and protecting the battery from unsafe

thermal conditions.

Figure 2.

Basis application schematic

Figure 1.

Minimum application size