General Description
The MAX17035/MAX17435/MAX17535 integrated multi chemistry battery chargers IC simplify construction of accurate and efficient chargers. The MAX17035/MAX17435/MAX17535 provide SMBusK-programmable charge current, charge voltage, input current limit, relearn voltage, and digital readback of the IINP voltage. The MAX17035/ MAX17435/MAX17535 utilize a charge pump to control the adapter selection n-channel MOSFETs when the adapter is present. When the adapter is absent, the charge pump is shut down and a p-channel MOSFET selects the battery.
The MAX17035/MAX17435/MAX17535 provide up to 7A of charge current to 2, 3, or 4 lithium-ion (Li+) cells in series. The charge current, and input current-limit sense amplifiers have low offset errors and can use 10mI sense resistors. The MAX17035/MAX17435/MAX17535 fixed-inductor ripple architecture significantly reduces component size and circuit cost.
The MAX17035/MAX17435/MAX17535 provide a digital output that indicates the presence of the adapter, an analog output that indicates the adapter or battery current, depending upon the presence or absence of the adapter, and a digital output that indicates when the adapter current exceeds a user-defined threshold.
The MAX17035 operates with a switching frequency of 1.2MHz. The MAX17435 switches at 850kHz, and the MAX17535 switches at 500kHz.
The MAX17035/MAX17435/MAX17535 are available in a small, 4mm x 4mm x 0.75mm 24-pin, lead-free QFN package. An evaluation kit is available.

FEATUREs
♦ Low-Cost SMBus Charger
♦ High Switching Frequency (1.2MHz, 0.85MHz, 0.5MHz)
♦ Internal Boost Switches
♦ SMBus-Programmable Charge Voltage, Input Current Limit, Charge Current, Relearn Voltage, and Digital IINP Readback
♦ Single-Point Compensation
♦ Automatic Selection of System Power Source
   Adapter n-channel MOSFETs Driven by an Internal Dedicated Charge Pump
   Adapter Soft-Start
♦ ±0.4% Accurate Charge Voltage
♦ ±2.5% Accurate Input Current Limiting
♦ ±3% Accurate Charge Current
♦ Monitor Outputs for
   AC Adapter Current (±2% Accuracy)
   Battery Discharge Current (±2% Accuracy)
   AC Adapter Presence
♦ AC Adapter Overvoltage Protection
♦ 11-Bit Battery Voltage Setting
♦ 6-Bit, Charge-Current Setting/Input Current Setting
♦ Improved IINP Accuracy at Low Input Current

APPLICATIONs
  Notebook Computers
  PDAs and Mobile Communicators
  2- to-4 Li+ Cell Battery-Powered Devices