LTC3458L

1

3458lf

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO

■

Inrush Current Limiting and Output Disconnect

■

Programmable/Synchronizable Fixed Frequency

Operation up to 1.5MHz

■

Current Mode Control with Programmable Soft-Start

Period and Peak Current Limit

Ω N-Channel and 0.3Ω P-Channel Switches

■

Ultralow Quiescent Currents: 12

µA Sleep, <1µA in

Shutdown

× 3mm Thermally Enhanced DFN

Package

■

Point-of-Load Regulators

■

MP3 Players

1.7A, 1.5MHz Synchronous

Step-Up DC/DC Converter

with Output Disconnect

The LTC

frequency, step up DC/DC converter with true output

disconnect and inrush current limiting. The LTC3458L is

rated for up to 6V output and includes a 0.2

Ω N-channel

MOSFET switch and a 0.3

Ω P-channel MOSFET synchro-

nous rectifier. The LTC3458L is well suited for battery

powered applications and includes programmable output

voltage, switching frequency and loop compensation. The

oscillator frequency can be set up to 1.5MHz or synchro-

nized to an external clock.

Quiescent current is only 12

µA during Burst Mode opera-

tion maximizing battery life in portable applications. The

Burst Mode current threshold, peak current limit, and soft-

start are externally programmable. Other features include

<1

µA shutdown current, antiringing control, and thermal

limit. The LTC3458L is available in a low profile (0.75mm),

4mm

× 3mm 12-pin DFN package.

Li-Ion to 5V at 1MHz

GND/PGND

SHDN

SYNC

SW

FB

COMP

SS

BURST

LTC3458L

Li Ion

3.1V TO 4.2V

2.2

µF

7.4

µH

ON OFF

200k

84.5k

133k

324k

33k

0.01

µF

0.01

µF

560pF

10pF

10pF

1M

22

µF

X5R

5V

750mA

3458L TA01a

LOAD CURRENT (mA)

0.1

100

95

90

85

80

75

70

65

60

1000

100

10

1

0.1

110

3458L TA01b

100

1000

POWER

LOSS

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

Burst Mode is a registered trademark of Linear Technology Corporation.

All other trademarks are the property of their respective owners.

Protected by U.S. Patents including 5481178, 6304066, 6580258, 5511131, 6498466