GENERAL DESCRIPTION
The ADP3804 is a complete Li-Ion battery charging IC. The device combines high output voltage accuracy with constant current control to simplify the implementation of Constant Current, Constant-Voltage (CCCV) chargers. The ADP3804 is available in two options. The ADP3804-12.6 guarantees the final battery voltage to 12.6 V ± 0.6%, the ADP3804-12.5 guarantees 12.525 V ± 0.6% and the ADP3804 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 drop out 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 boosted synchronous driver allows the use of two NMOS transistors for lower system cost.

FEATURES
   Li-Ion Battery Charger
   Fixed 12,525 V, 12.600 V, or Adjustable Battery
      Voltage
   High End-of-Charge Voltage Accuracy
      ±0.4% @ +25°C
      ±0.6% @ 5°C to 55°C
      ±0.75% @ 0°C to 85°C
   Programmable Charge Current with
      Rail-to-Rail Sensing
   System Current Sense with Reverse Input Protection
   Softstart Charge Current
   Undervoltage Lockout
   Boosted Synchronous Drive For External NMOS
   Programmable Oscillator Frequency
   Oscillator SYNC Pin
   Constant Current/Constant Voltage Flag
   Trickle Charge
  
APPLICATIONS
   Portable Computers
   Fast Chargers