Tiny Charger IC Delivers Maximum Current

( 1 May 2009 )

AnalogicTech’s AAT3620 is a fully integrated single-cell Lithium-ion battery charger capable of supplying up to 2A charge current in a small 3mm x 3mm TDFN package. This innovative dual mode solution provides a high efficiency switching charger during constant current (CC) and constant voltage (CV) mode. To minimize EMI and RFI emission, the device switches to linear mode during CV mode where power dissipation is at a minimum. It is a dual mode, PWM switching and linear mode charger designed to maximize charge efficiency. Operating across a 4.3V to 6.0V input range, the device performs battery charging using a 1.5MHz PWM converter. During CC and most of CV mode the device delivers up to 2A. When the current dips below 300mA in CV mode, the device automatically switches to a low noise linear mode minimizing noise, EMI and RFI emission. It also features programmable end of charge using external resistor, built-in reverse blocking, a 1 percent constant voltage mode regulation and an integrated programmable charging timer. Over-voltage, over-current and over-temperature protection circuits monitor charge state and battery charge temperature for fault conditions. The charger IC also adds a status monitor output pin to indicate battery charge status and power source status via a display LED.

Advanced Analogic Technologies Inc.