Cost-Saving, Multichemistry, Battery Charger System

Universal Charger with Low-Cost µC or Stand-Alone Li+ Charger

Please check latest availability status for a specific part variant.


The MAX846A 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 MAX846A 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 MAX846A 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.
MAX846A: Typical Operating Circuit MAX846A: Typical Operating Circuit Enlarge+

Key Features

  • 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


  • Cell Phones
  • Desktop Cradle Chargers
  • Handheld Instruments (PDAs, Palmtops)
  • Li+ Battery Packs
  • Li+-Ion/NiMH/NiCd Multichemistry Battery Chargers
  • Notebook Computers

See parametric specs for Battery Chargers (74)

Part NumberLithium Ion CellsProtected VIN
Charging VIN
Charge Rate Set byMax. ICHG
Charge TerminationCharge RegulationOper. Temp.
maxmaxSee Notes
Current Limit
Max. Voltage
Linear-40 to +85
$3.49 @1k

Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX846AEVKIT: Evaluation Kit for the MAX846A
Product Reliability Reports: MAX846A.pdf 
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

Quality Management System >
Environmental Management System >


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