LT3653

1

3653f

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

1.2A, HV Input Regulator

with Output Current Limit for

Battery Charger Applications

regulator with programmable output current limit. Typically,

it is used with battery charger power path controllers to

pre-regulate the output and optimize the battery charger

efficiency. Output current limit provides accurate control

over system power dissipation.

The wide operating input voltage range of 7.5V to 30V

suits the LT3653 to a variety of input sources, including

unregulated 12V wall adapters, 24V industrial supplies,

Firewire and automotive power. Input overvoltage protec-

tion allows the LT3653 to handle 60V input transients.

tracking control, Bat-Track. The LT3653 will block output

discharge during an open or shorted input.

The HVOK pin indicates that the internal bias supplies

are present and no faults have occurred (i.e., overtem-

perature and input overvoltage and undervoltage). The

LT3653 includes a 1.5MHz frequency oscillator, internal

compensation, and an internal boost diode to minimize the

number of external components. The LT3653 is available

in an 8-lead (2mm

× 3mm) package with exposed pads

for low thermal resistance.

High Voltage Single-Cell Battery Charger Application

– Operation from 7.5V to 30V

– Overvoltage Lockout Protects Circuit Through 60V

Transients

Chargers to Maximize Efficiency

× 3mm DFN Package

PDAs

Efficiency vs Load Current

7.5V TO 30V

TRANSIENT

TO 60V

0.1μF

SINGLE-CELL

Li-Ion

1.2A

SYSTEM

LOAD

10μF

4.7μH

3653 TA01a

LT3653

LTC4098

OUT

BAT

GND

BOOST

SW

HVOK

WALL

4.7μF

27.4k

+

, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.

Bat-Track is a trademark of Linear Technology Corporation. All other trademarks are the

property of their respective owners.

OUTPUT CURRENT(A)

0.1

100

90

70

50

80

60

40

0.7

3653 TA01a

1.1

1.3

0.9

0.5

0.3