The ADP3806 is a complete Li-Ion battery-charging IC. The
device combines high output voltage accuracy with constant
current control to simplify the implementation of constantcurrent,
constant-voltage (CCCV) chargers. The ADP3806 is
available in three options: The ADP3806-12.6 guarantees the
final battery voltage selected is 12.6 V or 16.8 V ± 0.6%, the
ADP3806-12.5 guarantees 12.525 V/16.7 V ± 0.6%, and the
ADP3806 is adjustable using two external resistors to set the
battery voltage. The current sense amplifier has rail-to-rail inputs
to accurately operate under low dropout and short-circuit conditions.
The charge current is programmable with a dc voltage on
ISET. A second differential amplifier senses the system current
across an external sense resistor and outputs a linear voltage
on the ISYS pin. The bootstrapped synchronous driver allows
the use of two NMOS transistors for lower system cost.