General Description

The MAX1909/MAX8725 highly integrated control ICs simplify construction of accurate and efficient multichemistry battery chargers. The MAX1909/MAX8725 use analog inputs to control charge current and voltage, and can be programmed by a host microcontroller (µC) or hardwired. High efficiency is achieved through use of buck topology with synchronous rectification.

Features

♦ ±0.5% Accurate Charge Voltage (0°C to +85°C)

♦ ±3% Accurate Input Current Limiting

♦ ±5% Accurate Charge Current

♦ Programmable Charge Current >4A

♦ Automatic System Power-Source Selection

♦ Analog Inputs Control Charge Current and Charge Voltage

♦ Monitor Outputs for Current Drawn from AC Input Source AC Adapter Presence

♦ Up to 17.65V (max) Battery Voltage

♦ Maximum 28V Input Voltage

♦ Greater than 95% Efficiency

♦ Charge Any Battery Chemistry: Li+, NiCd, NiMH, Lead Acid, etc.

Applications

  Notebook and Subnotebook Computers

  Hand-Held Data Terminals