LTC3315A

1

Rev. A

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TYPICAL APPLICATION

FEATURES

DESCRIPTION

Dual 5V, 2A Synchronous Step-Down

DC/DCs in 2mm

× 2mm LQFN

The LTC®3315A features dual 2A monolithic synchro-

nous step-down converters operating from a 2.25V to

5.5V input supply in one package for space-constrained

applications with demanding performance requirements.

Using constant frequency, peak current mode control at

switching frequencies up to 3MHz with a minimum on-

time as low as 25ns, both bucks achieve high efficiency

and fast transient response in a very small application

footprint.

The LTC3315A operates in forced continuous or pulse

high efficiency at light loads. The common buck switching

frequency is 2MHz and can be synchronized to an external

oscillator via the MODE/SYNC pin.

The LTC3315A can regulate outputs as low as 500mV.

Other features include precision enable thresholds, a

PGOOD signal, output overvoltage protection, thermal

shutdown, output short-circuit protection, and up to 100%

duty cycle operation for low dropout. The LTC3315A is

available in a compact 2mm × 2mm LQFN package.

Efficiency vs Load Current

Dual 2MHz 2A Buck Regulators

APPLICATIONS

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Dual Outputs Each with 2A Output Current

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High Efficiency: 19mΩ NMOS and 75mΩ PMOS

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Wide Bandwidth, Fast Transient Response

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Switching Frequency Synchronizable Up to 3MHz

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Peak Current Mode Control

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Minimum On-Time: 25ns

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Safely Tolerates Inductor Saturation in Overload

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Shutdown Current: 1.2µA

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Precision 400mV Enable Thresholds

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Internal Soft-Start and Compensation

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Power Good Output

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Low Profile, Thermally Enhanced 12-Lead

2mm × 2mm × 0.74mm LQFN Package

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AEC-Q100 Qualified for Automotive Applications

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Servers, Telecom Supplies, Optical Networking

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Distributed DC Power Systems (POL)

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FPGA, ASIC, µP Core Supplies

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Industrial/Automotive/Communications

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880nH

33µF

140k

100k

6.8pF

10µF

1µH

261k

100k

10µF

22µF

4.7pF

SW1

FB1

SW2

FB2

PGOOD

3315A TA01a

EN2

MODE/SYNC

GND

EN1

LTC3315A

2.25V TO 5.5V

1.2V, 2A

1.8V, 2A

EFFICIENCY

POWER LOSS

LOAD CURRENT (A)

1m

10m

100m

1 2

0

10

20

30

40

50

60

70

80

90

100

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

3315A TA01b

L = 880nH, L DCR = 19mΩ

Burst Mode OPERATION