LTC3621/LTC3621-2

1

3621f

For more information www.linear.com/LTC3621

Typical applicaTion

FeaTures

DescripTion

17V, 1A Synchronous

Step-Down Regulator with

3.5µA Quiescent Current

The LTC®3621/LTC3621-2 is a high efficiency 17V, 1A

synchronous monolithic step-down regulator. The switch-

ing frequency is fixed to 1MHz or 2.25MHz. The regulator

features ultralow quiescent current and high efficiencies

The step-down regulator operates from an input voltage

range of 2.7V to 17V and provides an adjustable output

current. A user-selectable mode input is provided to allow

the user to trade off ripple noise for light load efficiency;

Burst Mode operation provides the highest efficiency at

light loads, while pulse-skipping mode provides the low-

est voltage ripple.

List of LTC3621 Options

PART NAME

FREQUENCY

LTC3621

1.00MHz

Adjustable

LTC3621-2

2.25MHz

Adjustable

Efficiency and Power Loss vs Load

applicaTions

n

n

n

95% Max Efficiency

n

n

Constant Frequency (1MHz/2.25MHz)

n

n

1A Rated Output Current

n

±1% Output Voltage Accuracy

n

Current Mode Operation for Excellent Line and Load

Transient Response

n

Operation

n

Internal Compensation and Soft-Start

n

Overtemperature Protection

n

Compact 6-Lead DFN (2mm

× 3mm) Package or

8-Lead MSOPE Package with Power Good Output

and Independent SGND Pin

n

Portable-Handheld Scanners

n

Automotive Applications

n

Emergency Radio

L

, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks

and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the

property of their respective owners. Protected by U.S. Patents, including 5481178, 6580258,

6498466, 6611131, 6177787, 5705919, 5847554.

604k

22pF

1µF

22µF

3621 TA01a

4.7µH

2.5V

1A

191k

RUN

SW

2.7V TO 17V

LTC3621

GND

FB

MODE

10µF

LOAD CURRENT (A)

0.0001

0

10

30

40

50

100

70

0.001

0.01

3621 TA01b

20

80

90

60

0.0001

0.001

1.0

0.1

0.01

0.1

1

EFFICIENCY

POWER LOSS