The MAX1501 intelligent, constant-current, constant-voltage(CCCV), temperature-regulated battery chargercharges a single lithium-ion (Li+) cell or three-cellNiMH/NiCd batteries. The device integrates the current-senseresistor, PMOS pass element, and thermal-regulationcircuitry, while eliminating the reverse-blockingSchottky diode to create the simplest chargingsolution for hand-held equipment.

For single-cell Li+ batteries, the MAX1501 functions as astand-alone charger to control the charging sequencefrom the prequalification state through fast charge, top-off,and charge termination. With 3-cell NiMH/NiCdbatteries, the MAX1501 requires collaboration with amicrocontroller to determine the best charging algorithm.Proprietary thermal-regulation circuitry limits the die temperaturewhen fast charging or while exposed to highambient temperatures, allowing maximum charging currentwithout damaging the charger. The MAX1501 continuallysupplies a regulated output voltage underno-battery conditions, allowing battery changing withoutinterrupting system power.

The device achieves high flexibility by providing anadjustable fast-charge current, top-off current, safetytimer (disabled in the MAX1501Z), and thermal-regulationsetpoint. Other features include input power detection(active-low ACOK) and input under-/overvoltage protection.The MAX1501 provides active-low control inputs.

The MAX1501 accepts a 4.5V to 13V supply, butdisables charging when the input voltage exceeds6.5V, preventing excessive power dissipation. TheMAX1501 operates over the extended temperaturerange (-40°C to +85°C) and is available in a compact16-pin thermally enhanced 5mm x 5mm thin QFNpackage with 0.8mm profile.