REV. PrI

12/5/00

Information furnished by Analog Devices is believed to be accurate and

reliable. However, no responsibility is assumed by Analog Devices for its

use, nor for any infringements of patents or other rights of third parties

which may result from its use. No license is granted by implication or

otherwise under any patent or patent rights of Analog Devices.

=

Preliminary Technical Data

ADP3804

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

World Wide Web Site: http://www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 2000

PRELIMINAR

Y

TECHNICAL

DA

TA

High Frequency Switch Mode

Li-Ion Battery Charger

GENERAL DESCRIPTION

The ADP3804 is a complete Li-Ion battery charging IC. The

device combines high output voltage accuracy with constant

current control to simplify the implementation of Constant-

Current, Constant-Voltage (CCCV) chargers. The ADP3804 is

available in two options. The ADP3804-12.6 guarantees the

final battery voltage to 12.6 V ± 0.6%, the ADP3804-12.5

guarantees 12.525 V ± 0.6% and the ADP3804 is adjustable

using two external resistors to set the battery voltage. The

current sense amplifier has rail-to-rail inputs to accurately

operate under low drop out and short circuit conditions. The

charge current is programmable with a DC voltage on ISET. A

second differential amplifier senses the system current across an

external sense resistor and outputs a linear voltage on the ISYS

pin. The boosted synchronous driver allows the use of two

NMOS transistors for lower system cost.

FEATURES

Li-Ion Battery Charger

Li-Ion Battery Charger

Li-Ion Battery Charger

Li-Ion Battery Charger

Li-Ion Battery Charger

Fixed 12,525 V, 12.600 V, or Adjustable Battery

Fixed 12,525 V, 12.600 V, or Adjustable Battery

Fixed 12,525 V, 12.600 V, or Adjustable Battery

Fixed 12,525 V, 12.600 V, or Adjustable Battery

Fixed 12,525 V, 12.600 V, or Adjustable Battery

Voltage

Voltage

Voltage

Voltage

Voltage

High End-of-Charge Voltage Accuracy

High End-of-Charge Voltage Accuracy

High End-of-Charge Voltage Accuracy

High End-of-Charge Voltage Accuracy

High End-of-Charge Voltage Accuracy

0.4% @ +25

0.4% @ +25

0.4% @ +25

0.4% @ +25

0.4% @ +25 C

C

C

C

C

0.6% @ 5

0.6% @ 5

0.6% @ 5

0.6% @ 5

0.6% @ 5 C to 55

C to 55

C to 55

C to 55

C to 55 C

C

C

C

C

0.75% @ 0

0.75% @ 0

0.75% @ 0

0.75% @ 0

0.75% @ 0 C to 85

C to 85

C to 85

C to 85

C to 85 C

C

C

C

C

Programmable Charge Current with

Programmable Charge Current with

Programmable Charge Current with

Programmable Charge Current with

Programmable Charge Current with

Rail-to-Rail Sensing

Rail-to-Rail Sensing

Rail-to-Rail Sensing

Rail-to-Rail Sensing

Rail-to-Rail Sensing

System Current Sense with Reverse Input Protection

System Current Sense with Reverse Input Protection

System Current Sense with Reverse Input Protection

System Current Sense with Reverse Input Protection

System Current Sense with Reverse Input Protection

Softstart Charge Current

Softstart Charge Current

Softstart Charge Current

Softstart Charge Current

Softstart Charge Current

Undervoltage Lockout

Undervoltage Lockout

Undervoltage Lockout

Undervoltage Lockout

Undervoltage Lockout

Boosted Synchronous Drive For External NMOS

Boosted Synchronous Drive For External NMOS

Boosted Synchronous Drive For External NMOS

Boosted Synchronous Drive For External NMOS

Boosted Synchronous Drive For External NMOS

Programmable Oscillator Frequency

Programmable Oscillator Frequency

Programmable Oscillator Frequency

Programmable Oscillator Frequency

Programmable Oscillator Frequency

Oscillator SYNC Pin

Oscillator SYNC Pin

Oscillator SYNC Pin

Oscillator SYNC Pin

Oscillator SYNC Pin

Constant Current/Constant Voltage Flag

Constant Current/Constant Voltage Flag

Constant Current/Constant Voltage Flag

Constant Current/Constant Voltage Flag

Constant Current/Constant Voltage Flag

Trickle Charge

Trickle Charge

Trickle Charge

Trickle Charge

Trickle Charge

APPLICATIONS

Portable Computers

Portable Computers

Portable Computers

Portable Computers

Portable Computers

Fast Chargers

Fast Chargers

Fast Chargers

Fast Chargers

Fast Chargers

FUNCTIONAL BLOCK DIAGRAM

FUNCTIONAL BLOCK DIAGRAM

FUNCTIONAL BLOCK DIAGRAM

FUNCTIONAL BLOCK DIAGRAM

FUNCTIONAL BLOCK DIAGRAM

BATTERY

ADJUST

COMP

SD

BOOST

REGULATOR

+

SUPPLY

REGULATOR

UVLO

ADP3804

REG

CT

VCC BSTREG

BST

DRVH

SW

DRVL

PGND

AGND

OSCILLATOR

LIMIT

ISYS

ISET

BAT

ADJ

REFERENCE

+

BIAS

VREF

REF

gm1

gm2

SYNC

CCCV

INPUT

DIVIDER

ADP3804-12.6

ADP3804-12.5

VREF

AMP

1

AMP

2

CS+

SYS

CS

SYS+

BOOSTED

SYNCHRONOUS

DRIVER