The MAX1870AETJ+ is a step-up/step-down Li+ battery charger in 32 pin TQFN package. This multichemistry battery charger charges with battery voltages above and below the adapter voltage. This highly integrated charger requires a minimum number of external components, it uses a proprietary step-up/step-down control scheme that provides efficient charging. Analogue inputs control charge current, voltage and can be programmed by host or hardwired. It accurately charges two to four lithiumion (Li+) series cells at greater than 4A. A programmable input current limit is included which avoids overloading AC adapter when supplying load and battery charger simultaneously. This reduces the maximum adapter current which reduces cost and provides analogue outputs to monitor current drawn from AC adapter and charge current. A digital output indicates presence of an AC adapter. When adapter is removed IC consumes less than 1μA from battery. It is used in notebook and subnotebook computers.
Input voltage range is 8V to 28V
Operating temperature range from -40°C to 85°C
Highly flexible input voltage range works with affordable AC adapters
Step-up/step-down control scheme
Accurately charge Li+ or NiCd/NiMH batteries, battery voltage from 0V to 17.6V
±0.5% charge voltage accuracy, ±9% charge current accuracy & ±8% input current limit accuracy
Tune design to increase safety and efficiency, programmable maximum battery charge current
Analogue inputs control charge current, charge voltage and input current limit