AAT3685IWP-4.2-1-T1 データシートの表示（PDF） - Analog Technology Inc

部品番号

コンポーネント説明

メーカー

AAT3685IWP-4.2-1-T1

Lithium-Ion/Polymer Battery Charger

Analog Technology Inc 

BatteryManagerTM

Functional Block Diagram

PRODUCT DATASHEET

AAT3685

Lithium-Ion/Polymer Battery Charger

ADP/USB

PWRSEL

SETH

SETL

CHR

STAT1

STAT2

DATA

Charge

Reduction

Loop

Current

Compare

Constant

Current

Charge

Status

Reverse Blocking

Charge

Control

CV/

Precharge

UVLO

Over-

Temperature

Protect

BAT

Serial

Data

IC enable

Window

Comparator

80μA

TS

EN

Functional Description

The AAT3685 is a highly integrated single cell lithium-

ion/polymer battery charger IC designed to operate from

adapter or USB port VBUS supplies, while requiring a

minimum number of external components. The device

precisely regulates battery charge voltage and current

for 4.2V lithium-ion/polymer battery cells.

The AAT3685 is specifically designed for being powered

from a USB port VBUS supply, but it can also be powered

from any input voltage source capable supplying 4.5V to

5.5V for loads up to 1A. The AAT3685 constant charge

current can be externally programmed for two levels,

SETH and SETL, for maximum constant current charge

levels up to 1A. The SETH/L mode has an automatic

Charge Reduction Loop control to allow users to charge

the battery with limited available current from a port

while maintaining the regulated port voltage. This sys-

tem assures the battery charge function will not overload

the port while charging if other system demands also

share power with the respective port supply.

GND

Status monitor output pins are provided to indicate the

battery charge status by directly driving two external

LEDs. A serial interface output is available to report 14

various charge states to a system microcontroller.

Battery temperature and charge state are fully monitored

for fault conditions. In the event of an over-voltage or

over-temperature failure, the device will automatically

shut down, thus protecting the charging device, control

system, and the battery under charge. In addition to

internal charge controller thermal protection, the AAT3685

also provides a temperature sense feedback function (TS

pin) from the battery to shut down the device in the

event the battery exceeds its own thermal limit during

charging. All fault events are reported to the user either

by the simple status LEDs or via the DATA pin function.

Charging Operation

The AAT3685 has four basic modes for the battery

charge cycle and is powered from the input: pre-condi-

tioning/trickle charge; constant current/fast charge;

constant voltage; and end of charge. For reference,

Figure 1 shows the current versus voltage profile during

charging phases.

10

www.analogictech.com

3685.2007.12.1.4

Share Link: