LTC3245

1

3245f

For more information www.linear.com/LTC3245

Typical applicaTion

FeaTures

DescripTion

Low Noise, 250mA Buck-Boost

Charge Pump

The LTC®3245 is a switched capacitor buck-boost DC/DC

converter that produces a regulated output (3.3V, 5V or

adjustable) from a 2.7V to 38V input. The device uses

switched capacitor fractional conversion to maintain

regulation over a wide range of input voltage. Internal

circuitry automatically selects the conversion ratio to

optimize efficiency as input voltage and load conditions

vary. No inductors are required.

The unique constant frequency architecture provides a

lower noise output than conventional charge pump regu-

lators. To optimize efficiency at the expense of slightly

higher output ripple, the device has pin selectable Burst

Mode operation.

Low operating current (20μA with no load, 4μA in shut-

down) and low external parts count (three small ceramic

capacitors)maketheLTC3245ideallysuitedforlowpower,

spaceconstrainedautomotive/industrialapplications.The

deviceisshort-circuitandovertemperatureprotected,and

is available in thermally enhanced 12-pin MSOP and low

profile 3mm × 4mm 12-pin DFN packages.

Efficient Regulated 5V Output

applicaTions

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Automotive ECU/CAN Transceiver Supplies

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Industrial Housekeeping Supplies

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Low Power 12V to 5V Conversion

L

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

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

property of their respective owners.

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12V to 5V Efficiency = 81%

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Multimode Operation (2:1, 1:1, 1:2) with Automatic

Mode Switching

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Low Noise, Constant Frequency Operation

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Overtemperature and Short-Circuit Protection

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Operating Junction Temperature: 150°C Maximum

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Thermally Enhanced 12-Pin MSOP and Low Profile

12-Pin (3mm × 4mm) DFN Packages

3245 TA01b

90

70

60

80

50

30

20

40

10

400

300

250

350

200

100

50

150

0

0.1

100

1000

10

1

EFFICIENCY

SEL2

BURST

SEL1

OUTS/ADJ

PGOOD

GND

LTC3245

3245 TA01a

1µF

1µF

10µF

500k