The MAX846AEEE is a cost-saving multichemistry battery-charger system that comes in a space-saving 16-pin QSOP. This integrated system allows different battery chemistries (Li-Ion, NiMH or NiCd cells) to be charged using one circuit. In its simplest application, the MAX846AEEE is a stand-alone, current-limited float voltage source that charges Li-Ion cells. It can also be paired up with a low-cost microcontroller (μC) to build a universal charger capable of charging Li-Ion, NiMH, and NiCd cells. An internal 0.5%-accurate reference allows safe charging of Li-Ion cells that require tight voltage accuracy. The voltage- and current-regulation loops used to control a low-cost external PNP transistor (or P-channel MOSFET) are independent of each other, allowing more flexibility in the charging algorithms. The MAX846AEEE has a built-in 1%, 3.3V, 20mA linear regulator capable of powering the μC and providing a reference for the μC's analog-to-digital converters. An on-board reset notifies the controller upon any unexpected loss of power. The μC can be inexpensive, since its only functions are to monitor the voltage and current and to change the charging algorithms.
Feature
- Multichemistry Charger System (Li-Ion, NiMH, NiCd)
- Independent Voltage and Current Loops
- ±0.5% Internal Reference for Li-Ion Cells
- Lowers Cost:
- Stands Alone or Uses Low-Cost μC
- Built-In 1% Linear Regulator Powers μC
- Linear Regulator Provides Reference to μC ADCs
- Built-In μC Reset
- Controls Low-Cost External PNP Transistor or P-Channel MOSFET
- Space-Saving 16-Pin QSOP
- Charging-Current-Monitor Output
- < 1μA Battery Drain when Off
Applications
- Cell Phones
- Desktop Cradle Chargers
- Handheld Instruments (PDAs, Palmtops)
- Li+ Battery Packs
- Li+-Ion/NiMH/NiCd Multichemistry Battery Chargers
- Notebook Computers
