LTC3450

1

3450f

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO

The LTC

small thin film transistor (TFT) liquid crystal display (LCD)

panels. The device operates from a single Lithium-Ion cell,

2- to 3-cell alkaline input or any voltage source between

1.5V and 4.6V.

The synchronous boost converter generates a low noise,

high efficiency 5.1V, 10mA supply. Internal charge pumps

are used to generate 10V, 15V, and –5V, –10V or –15V.

Output sequencing is controlled internally to insure proper

initialization of the LCD panel.

A master shutdown input reduces quiescent current to

<2

µA and quickly discharges each output for rapid turn off

of the LCD panel. The LTC3450 is offered in a low profile

(0.8mm max), 3mm

× 3mm 16-pin QFN package, mini-

mizing the solution profile and footprint.

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Cellular Handsets with Color Display

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Handheld Instruments

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PDA

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

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Generates Three Voltages:

5.1V at 10mA

– 5V, –10, or –15V at 500

µA

10V or 15V at 500

µA

s

Better than 90% Efficiency

s

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Complete 1mm Component Profile Solution

s

s

All Outputs Disconnected and Actively Discharged in

Shutdown

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Low Noise Fixed Frequency Operation

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Frequency Reduction Input for High Efficiency in

Blank Mode

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Ultralow Quiescent Current: 75

µA (Typ) in Scan Mode

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Available in a 3mm

× 3mm 16-Pin QFN Package

Triple Output Power Supply

for Small TFT-LCD Displays

0.1

µF

2.2

µF

1.5V TO

4.6V

5.1V/10mA

VGH (3

15V/500

µA

VGL

–10V/500

µA

3450 TA01

0.1

µF

0.1

µF

11

7

8

10

14

13

V2X

V3X

SHDN

MODE

SW

LTC3450

GND

12

15

16

1

2

3

6

5

OFF ON

BLANK SCAN

47

µH

4

9

2.2

µF

0.47

µF

0.1

µF

0.1

µF

5.1V, –10V, 15V Triple Output TFT-LCD Supply

1.5

100

95

90

85

80

75

70

3.0

4.0

3450 TA01b

2.0

2.5

3.5

4.5

5.0

100

µH

47

µH

5mA LOAD