AnalogicTech family of extremely small USB/AC battery charger ICs support charge currents up to 1A
AnalogicTech has introduced a comprehensive line of USB/AC battery charger ICs for portable systems operating off single-cell 4.2V (4.375V) Lithium Ion/Polymer batteries. Integrating a wide array of features into a highly compact footprint and requiring just a single external component, the new devices offer a complete USB/AC charging function in packages as small as 2.0 x 2.1 mm.
Designers of today’s cellular handsets, Bluetooth headsets, MP3 players and digital cameras must offer comprehensive USB/AC charging capability while sacrificing as little of their limited product footprint as possible. By offering a wide array of choices from comprehensive solutions with integrated digital thermal regulation to relatively basic alternatives with automatic trickle charge and battery pre-conditioning options in extremely compact packages, the product family enables the optimal solution in the smallest footprint for their target market.
The AAT3683 offers the most comprehensive feature set in the new product family. This highly integrated, single input USB/AC charger supports programmable charge currents up to 1A. Operating off a voltage input range of 4.0V to 6.5V, the AAT3683 integrates a charging device, reverse blocking diode and current sensing to regulate battery charge voltage and current for 4.2V (4.375V) Li-ion/polymer battery cells.
The battery charger IC includes a digital thermal regulation circuit developed and patented by AnalogicTech that automatically reduces the charging current when the internal temperature of the die exceeds a preset limit to prevent the device from thermal shutdown. This feature helps minimise charge time by maintaining the maximum possible battery charging current for a given set of input to output, power dissipation and ambient temperature conditions.
The AAT3683 also adds an integrated charge timer that automatically terminates charging functions if a defective battery cell does not accept a charge over a preset period of time.
The AAT3684 is a single-input USB/AC adapter charger with charge current programmable from 15 to 500mA. The device offers automatic trickle charge for battery pre-condition as a standard feature. The optional AAT3684-1 version comes without the trickle charge capability.
The AAT3681A is a derivative of the AAT3681 that was announced by AnalogicTech last year. Designed for space-constrained, portable applications requiring up to 500mA from either a USB or AC source, the AAT3681A comes in a highly compact 2.0 x 2.1mm SC70JW package. Unlike its predecessor, this battery charger IC is also available with a variety of trickle charge, active enable high and low, and charge termination threshold current options.
Each of the new charger ICs offer overvoltage, short-circuit and over temperature protection. The AAT3683 adds over-current protection.
All three devices are specified across the -40 to +85 degrees C temperature range. The AAT3681A is available in a Pb-free, 8-pin, 2 x 2.1 mm SC70JW package. The AAT3683 is available in Pb-free, 10-pin 2.2 x 2.2 mm STDFN and 16-pin QFN-33 packages. The AAT3684 is available in a 10-pin 2.2 x 2.2 mm STDFN package.
Phil Dewsbury, Advanced Analogic Technologies, Inc., Europe Newbury, UK Tel: +44 (0) 1189 657763