LT3682

1

3682f

TYPICAL APPLICATION

DESCRIPTION

1A Micropower Step-Down

Switching Regulator

The LT

2.2MHz) monolithic buck switching regulator that accepts

input voltages up to 36V. A high efficiency 0.5Ω switch is

included on the device along with a boost diode and the

necessary oscillator, control, and logic circuitry. Current

mode topology is used for fast transient response and good

loop stability. A SYNC pin allows the user to synchronize the

part to an external clock, and to choose between Low Ripple

Burst Mode operation and standard PWM operation.

The Low Ripple Burst Mode maintains high efficiency at

low output currents while keeping output ripple below

15mV in typical applications. Shutdown reduces input

supply current to less than 1μA while a resistor and

capacitor on the RUN/SS pin provide a controlled output

voltage ramp (soft-start). A power good flag signals when

Protection circuitry senses the current in the power switch

and external Schottky catch diode to protect the LT3682

against short-circuit conditions. Frequency foldback and

thermal shutdown provide additional protection.

The LT3682 is available in a 12-Pin 3mm

× 3mm DFN with

exposed pad for low thermal resistance.

5V Step-Down Converter

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

is a trademark of Linear Technology Corporation. All other trademarks are the property of their

respective owners.

FEATURES

APPLICATIONS

Operation from 3.6V to 36V

Overvoltage Lockout Protects Circuits through

60V Transients

× 3mm

DFN Package

Efficiency

6.9V TO 36V

TRANSIENT TO 60V

5V

2.2μF

16.2k

40.2k

470pF

102k

10μF

536k

0.22μF

10μH

3682 TA01

OFF

ON

BD

GND

PGND

LT3682

RUN/SS

SYNC

PG

BOOST

SW

DA

FB

f = 800kHz

LOAD CURRENT (A)

0

50

60

70

80

90

100

0.2

0.4

0.6

0.8

1

L = 10µH

f = 800 kHz

3682 TA01b