LTC3313

1

Rev. 0

For more information www.analog.com

Document Feedback

TYPICAL APPLICATION

FEATURES

DESCRIPTION

The LTC®3313 is a very small, low noise, monolithic

step-down DC/DC converter capable of providing up to

15A of output current from a 2.25V to 5.5V input supply.

The device employs the Silent Switcher architecture to

achieve both low EMI and high efficiency at switching

frequencies as high as 5MHz. For systems with higher

power requirements, multiphasing parallel converters is

readily implemented.

The LTC3313 uses a constant frequency, peak current

mode control architecture for fast transient response. A

500mV reference allows for low voltage outputs. 100%

duty cycle operation delivers low drop out.

Other features include a power good signal when the

output is in regulation, a precision enable threshold, output

overvoltage protection, thermal shutdown, a temperature

monitor, clock synchronization, mode selection, and

output short circuit protection. The device is available in

a compact 18-pin 3mm × 3mm LQFN package.

1.2V, 15A Step-Down Converter

Efficiency vs Load Current

APPLICATIONS

n

Layout Compatible with LTC3310/LTC3311 Family

n

Silent Switcher® Architecture

n

Ultralow EMI Emissions

n

High Efficiency: 3mΩ NMOS and 8mΩ PMOS

n

Wide Bandwidth, Fast Transient Response

n

Safely Tolerates Inductor Saturation in Overload

n

VIN Range: 2.25V to 5.5V

n

VOUT Range: 0.5V to VIN

n

VOUT Accuracy: ±1% with Remote Sense

n

Peak Current Mode Control

n

Minimum On-Time: 35ns

n

Programmable Frequency to 5MHz

n

Shutdown Current: 1µA

n

Precision 400mV Enable Threshold

n

Output Soft-Start with Voltage Tracking

n

Power Good Output

n

Die Temperature Monitor

n

Configurable for Paralleling Power Stages

n

Thermally-Enhanced 3mm × 3mm LQFN Package

n

AEC-Q100 Qualified for Automotive Applications

n

Automotive/Industrial/Communications

n

Servers, Telecom Power Supplies

n

Distributed DC Power Systems (POL)

n

FPGA, ASIC, µP Core Supplies

All registered trademarks and trademarks are the property of their respective owners.

3313 TA01a

140k

47µF

×3

100k

VOUT

1.2V

15A

6.8pF

274k

22µF

22µF

0.1µF

SW

FB

AGND

RT

EN

MODE/SYNC

PGOOD

SSTT

ITH

0.1µF

0.1µF

15k

470pF

VIN

VIN

3V TO 5.5V

PGND

LTC3313

80nH

1F

VIN

5V, 15A Synchronous Step-Down

Silent Switcher in 3mm × 3mm LQFN

EFFICIENCY

POWER LOSS

VIN = 3.3V

VOUT = 1.2V

fSW = 2MHz

COILCRAFT XEL4020-800MEC

LOAD CURRENT (A)

0

2.5

5

7.5

10

12.5

15

0

10

20

30

40

50

60

70

80

90

100

0

0.4

0.8

1.2

1.6

2.0

2.4

2.8

3.2

3.6

4.0

3313 TA01a