Product category:
Power Supply ICs and Controllers
News Release from: Advanced Analogic Technologies | Subject: AAT2550/1
Edited by the Electronicstalk Editorial
Team on 17 November 2006
Charger and two convertors come together
Highly integrated device saves PCB space by combining a 1A battery charger with two 600mA step-down convertors in a small 4 x 4mm QFN package.
AnalogicTech, a developer of power management semiconductors for mobile consumer electronic devices, has introduced the AAT2550, a highly integrated power management IC for smart phones, portable media/music players, and other handheld computing devices Targeted at portable systems powered by single-cell lithium ion/polymer batteries rated up to 1500mAh, the highly integrated device saves PCB space by combining a 1A battery charger with two 600mA step-down convertors in a small 4 x 4mm QFN package
This article was originally published on Electronicstalk on 16 Jun 2004 at 8.00am (UK)
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By integrating AnalogicTech's digital thermal control loop into the battery charger, the AAT2550 senses when the IC is self-heating and automatically throttles back the battery charge current to decrease the power being dissipated without impacting the buck convertors and thus preventing a processor interrupt or system shutdown.
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Moreover, by determining the highest level of charge current the system can maintain, this feature plays a major role in minimising charge time.
For systems that require charging from either AC or USB sources, AnalogicTech is also introducing the AAT2551 SystemPower IC.
Similar to the AAT2550, this device features a 1A charger and two 600mA buck convertors.
However, the charger in the AAT2551 offers dual-path AC adapter and USB charging.
The USB path offers two user-programmable charge currents to support USB low and high charge levels.
The charger in the AAT2551 also adds AnalogicTech's innovative charge reduction function that automatically reduces charge current only to the extent necessary to preserve the integrity of the USB host voltage.
By allowing users to charge the battery with the maximum available current from the USB port while keeping the port voltage regulated, this feature ensures that the battery charger will not overload the USB port even when other system applications share power with the port supply, and that the battery charge time is minimised.
The AAT2551 will be available in Q1 2007.
Both the AAT2550 and AAT2551 feature a constant current/constant voltage battery charger with the charge current programmable, via an external resistor, from 100mA to 1A.
The charger offers an integrated pass device, reverse blocking protection, high accuracy, digital thermal regulation, charge status and charge termination.
It also adds overvoltage, overcurrent and thermal protection.
To help reduce the size of external components, the two 600mA step-down convertors in the AAT2550/51 operate at a 1.4MHz switching frequency.
Both devices operate off a 2.7 to 5.5V input and feature independent input, enable and feedback pins.
Each convertor consumes just 27uA of no-load quiescent current.
Both the AAT2550 and the AAT2251 are specified over the -40 to +85C temperature range.
The AAT2550 is available in a Pb-free, thermally enhanced QFN44-24 package, whereas the AAT2551 comes in a Pb-free, thermally enhanced TQFN44-28 package.
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