LTC3539/LTC3539-2

1

3539f

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

2A, 1MHz/2MHz

Synchronous Step-Up

DC/DC Converters

DC/DC converters with output disconnect. Synchronous

rectification enables high efficiency in the low profile

2mm

× 3mm DFN package. Battery life is extended with

a 700mV start-up voltage and operation down to 500mV

once started.

A switching frequency of 1MHz (LTC3539) or 2MHz

(LTC3539-2) minimizes solution footprint by allowing the

use of tiny, low profile inductors and ceramic capacitors.

The current mode PWM design is internally compensated,

reducing external parts count. The LTC3539/LTC3539-2

feature a pin-enabled automatic Burst Mode operation at

light load conditions. Anti-ring circuitry reduces EMI by

damping the inductor in discontinuous mode. Additional

features include a low shutdown current of under 1μA and

thermal overload protection.

The LTC3539/LTC3539-2 are offered in a 2mm

× 3mm ×

0.75mm DFN package.

Battery

Frequency Operation

× 3mm × 0.75mm) DFN Package

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

All other trademarks are the property of their respective owners.

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3539 TA01b

POWER LOSS

EFFICIENCY

FREQUENCY = 1MHz

FREQUENCY = 2MHz

Efficiency and Power Loss vs

Load Current

3539 TA01a

LTC3539

SW

2.2μF

3.3V

600mA

1.8V TO 3.6V

4.7μH

MODE

SHDN

FB

PGND

GND

562k

1M

22μF

22pF

BURST

PWM

ON

OFF