Battery charger IC for single and dual cell applications

A growing number of products, from Portable Media Players (PMPs) and digital cameras to point of sale (POS) solutions and high-end handsets are powered today by two Li-Ion cells connected in series. By supporting input voltages up to 13.2V, the AAT3663 offers designers the opportunity to replace larger and more expensive discrete charging solutions with a high integrated and more cost effective alternative.



The AAT3663 operates across a 4.0V to 13.2V input voltage range and supports user programmable charge current from 100mA up to 1A via an external resistor. Quiescent current is less than 6microAmps.

The device features an intelligent digital thermal loop charge reduction circuit that optimises battery charge rate by constantly measuring die temperature and adjusting the charge current to compensate for thermal conditions. Unlike many competitive charger ICs, this closed loop thermal management system allows the charger to continue charging even under harsh environmental conditions, therefore minimising charge time.



The charger IC also features a programmable charge termination current feature that sends the device into sleep mode if the charging current dips below a pre-defined threshold. An integrated programmable charge timer can be used to shut down charging functions if a defective battery cell or a disconnection to the battery current path is detected.



The AAT3663 continuously monitors battery temperature and charge state for fault conditions. To protect the charging device and the battery under charge, integrated over-temperature, short-circuit, over-voltage and over-current protection circuits automatically shuts down the device if a fault occurs.

The AAT3663 is fabricated in AnalogicTech’s proprietary ModularBCD process. Compared to linear-IC legacy fabs and generic digital CMOS foundries, ModularBCD provides more cost-effective, modular fabrication of analogue, power and mixed-signal ICs by monolithically integrating fully isolated CMOS at multiple voltages, complementary bipolar transistors, and robust power devices. This process avoids complex and expensive techniques such as epitaxy and high-temperature diffusion. Devices manufactured in ModularBCD offer higher efficiency, smaller size and higher levels of integration than those fabricated in many other processes.



Specified for operation across the -40 C to +85 C temperature range, the AAT3663 is available in a thermally enhanced 14-pin, 3x3mm TDFN package.