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LT1616

600mA, 1.4MHz Step-Down

Switching Regulator

in SOT-23

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

The LT

converter with internal 0.6A power switch, packaged in a

tiny 6-lead SOT-23. The wide input range of 3.6V to 25V

makes the LT1616 suitable for regulating a wide variety of

power sources, from 4-cell batteries and 5V logic rails to

unregulated wall transformers and lead-acid batteries. Its

high operating frequency allows the use of tiny, low cost

inductors and ceramic capacitors. With its internal com-

pensation eliminating additional components, a complete

400mA step-down regulator fits onto 0.15 square inches

of PC board area.

The constant frequency current mode PWM architecture

and stable operation with ceramic capacitors results in

low, predictable output ripple. Current limiting provides

protection against shorted outputs. The low current (<1

µA)

shutdown provides complete output disconnect, enabling

easy power management in battery-powered systems.

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Wide Input Range: 3.6V to 25V

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5V at 400mA from 7V to 25V Input

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3.3V at 400mA from 4.7V to 25V Input

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Fixed Frequency 1.4MHz Operation

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Uses Tiny Capacitors and Inductors

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Internally Compensated

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Low Shutdown Current: <1

µA

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Tiny 6-Lead SOT-23 Package

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Wall Transformer Regulation

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Local Logic Supply Conversion:

12V to 5V

12V or 5V to 3.3V, 2.5V or 1.8V

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Distributed Supply Regulation

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Digital Cameras

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Battery-Powered Equipment

3.3V Step-Down Converter

BOOST

GND

FB

SHDN

SW

5

4.5V TO 25V

OFF ON

4

1

6

C3

0.01

µF

D1

D2

L1

10

µH

23

R2

10k

R1

16.5k

LT1616

C2

10

µF

1616 TA01

C1

1

µF

3.3V

C1: TAIYO-YUDEN TMK316BJ105

C2: TAIYO-YUDEN JMK316BJ106ML

D1: ON SEMICONDUCTOR MBR0530

D2: 1N4148

L1: SUMIDA CR43-100

Efficiency

LOAD CURRENT (mA)

0

80

90

100

300

400

1616 G02

70

60

100

200

500

50

40

30

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO