MAX846A

19-1121; Rev 0; 9/96 KIT ATION EVALU E L B A AVAIL Cost-Saving Multichemistry Battery-Charger System ____________________________Features o o o o 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 o Space-Saving 16-Pin QSOP o Charging-Current-Monitor Output o <1µA Battery Drain when Off _______________General Description The MAX846A is a cost-saving multichemistry batterycharger 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 MAX846A is a standalone, 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 MAX846A has a built-in 1%, 3.3V, 20mA linear regulator capable of powe...