AAT3689 Просмотр технического описания (PDF) - Advanced Analogic Technologies

Номер в каталоге

Компоненты Описание

производитель

AAT3689

0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger

Advanced Analogic Technologies 

AAT3689

0.5A/1.0A USB Port/Adapter

Lithium-Ion/Polymer Battery Charger

Functional Block Diagram

USB

USBSET

Current

Compare

Reverse Blocking

CV/

Precharge

ADPSET

ADP

STAT1

STAT2

EN

Constant

Current

Current

Compare

Charge

Control

UVLO

Over-

Temperature

Protection

BAT

Voltage

Sense

Charge

Status

Reverse Blocking

80uA

Window

Comparator

IC Enable

Watchdog

Timer

TS

CT

GND

Functional Description

The AAT3689 is a highly integrated single cell lithi-

um-ion/polymer battery charger IC designed to

operate with USB port and AC adapter inputs,

while requiring a minimum number of external

components. The AAT3689 precisely regulates

battery charge voltage and current for 4.2V lithium-

ion/polymer battery cells.

The adapter charge input constant current level

may be programmed up to 1.0A for rapid charging

applications. In the absence of a high current

adapter input source, the AAT3689 may be pow-

ered from a USB port VBUS supply. The USB con-

stant charge current can be externally pro-

grammed for maximum constant current charge

levels up to 500mA. The USB charge function is

automatically disabled when an adapter input

power source greater than 4.5V is present.

10

Status monitor output pins are provided to indicate

the battery charge status by directly driving two

external LEDs.

Battery temperature and charge state are fully mon-

itored for fault conditions. In the event of an over-

voltage or over-temperature failure, the device will

automatically shut down, thus protecting the charg-

ing device, control system, and the battery under

charge. In addition to internal charge controller ther-

mal protection, the AAT3689 also provides a tem-

perature sense feedback function (TS pin) from the

battery to shut down the device in the event the bat-

tery exceeds its own thermal limit during charging.

Charging Operation

Regardless of which charge input function is select-

ed (i.e., either the adapter input or USB input), the

AAT3689 has four basic modes for the battery

charge cycle: pre-conditioning/trickle charge; con-

stant current/fast charge; constant voltage; and end

of charge (see Figure 1).

3689.2006.11.1.0

Share Link: