GENERAL DESCRIPTION

The ADP3808 is a complete Li-Ion battery charging controller for 3- or 4-cell battery packs. The device combines accurate final battery charge voltage control with constant current control to simplify the implementation of constant-current, constant-voltage (CCCV) chargers.

The final battery charge voltage is programmable between 4.0 V to 4.5 V per cell, allowing the charging of various cell types. The charge current is programmable over a wide range from trickle

charging to full charging. The system current sense amplifier includes an ac adapter detection output to signal that the adapter is connected. The bootstrapped synchronous driver controls two N-channel MOSFET transistors for high efficiency charging at a low system cost.

The ADP3808 is specified over the extended commercial temperature range of 0°C to 100°C and is available in a 24-lead LFCSP package.

FEATURES

Selectable 3-cell or 4-cell operation

Adjustable 4.0 V to 4.5 V per cell

High end-of-charge voltage accuracy

±0.4 @ 25°C

±0.6 @ 5°C to 55°C

±0.8 @ 0°C to 100°C

Programmable charge current, including trickle charge

Bootstrapped synchronous drive for external N-channel MOSFETs

Programmable oscillator frequency

APPLICATIONS

Portable computers

Portable equipment