1

LTC3418

3418f

8A, 4MHz, Monolithic

Synchronous Step-Down

Regulator

with Adjustable Burst Clamp

QFN (5mm × 7mm) Package

DESCRIPTIO

FEATURES

APPLICATIO S

TYPICAL APPLICATIO

2.5V/8A Step-Down Regulator

The LTC

nous step-down DC/DC converter utilizing a constant

frequency, current mode architecture. It operates from an

input voltage range of 2.25V to 5.5V and provides a

regulated output voltage from 0.8V to 5V while delivering

up to 8A of output current. The internal synchronous

power switch increases efficiency and eliminates the need

for an external Schottky diode. Switching frequency is set

by an external resistor or can be synchronized to an

external clock. OPTI-LOOP

transient response to be optimized over a wide range of

loads and output capacitors.

The LTC3418 can be configured for either Burst Mode

operation or forced continuous operation. Forced continu-

ous operation reduces noise and RF interference while

Burst Mode operation provides high efficiency by reduc-

ing gate charge losses at light loads. In Burst Mode

operation, external control of the burst clamp level allows

the output voltage ripple to be adjusted according to the

requirements of the application. A tracking input in the

LTC3418 allows for proper sequencing with respect to

another power supply.

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

Burst Mode and OPTI-LOOP are registered trademarks of Linear Technology Corporation.

All other trademarks are the property of their respective owners.

Protected by U.S. Patents, including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131,

6724174.

Efficiency and Power Loss vs Load Current

100µF

0.2µH

LTC3418

RUN/SS

PGOOD

SW

PGND

SGND

332Ω

820pF

3418 TA01a

1000pF

100µF

×2

2.5V

8A

4.32k

1.69k

30.1k

2.2M

2.8V TO 5.5V

4.99k

LOAD CURRENT (A)

0.01

60

80

100

0.1

1

10

3418 TA01b

40

50

70

90

30

20

1000

100000

100

10000

10

1

EFFICIENCY

POWER LOSS