LTC3412

1

3412fb

The LTC

nous, step-down DC/DC converter utilizing a constant

frequency, current mode architecture. It operates from an

input voltage range of 2.625V to 5.5V and provides an

adjustable regulated output voltage from 0.8V to 5V while

delivering up to 2.5A of output current. The internal

synchronous power switch with 85mΩ on-resistance

increases efficiency and eliminates the need for an exter-

nal Schottky diode. Switching frequency is set by an

external resistor or can be sychronized to an external

clock. 100% duty cycle provides low dropout operation

extending battery life in portable systems. OPTI-LOOP

®

compensation allows the transient response to be opti-

mized over a wide range of loads and output capacitors.

The LTC3412 can be configured for either Burst Mode

®

operation or forced continuous operation. Forced con-

tinuous 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. To further maximize

battery life, the P-channel MOSFET is turned on continu-

ously in dropout (100% duty cycle).

with Adjustable Burst Clamp

and QFN Packages

2.5A, 4MHz, Monolithic

Synchronous Step-Down Regulator

Figure 1. 2.5V, 2.5A Step-Down Regulator

Efficiency vs Load Current

PGOOD

SW

LTC3412

PGND

SGND

RUN/SS

309k

2.7V TO 5.5V

1000pF

SYNC/MODE

1μH

4.7M

470pF

75k

100pF

100μF

2.5V

2.5A

15k

110k

392k

22μF

3412 F01

LOAD CURRENT (A)

0.001

100

80

60

40

20

0

10

3412 G01

Burst Mode OPERATION

FORCED CONTINUOUS

0.1

1

0.01

DESCRIPTIO

FEATURES

APPLICATIO S

TYPICAL APPLICATIO

, LT, LTC, LTM, Burst Mode and OPTI-LOOP are registered trademarks of Linear

Technology Corporation. All other trademarks are the property of their respective owners.