LTC3240-3.3/LTC3240-2.5

1

3240fb

3.3V or 2.5V Outputs

Step-Up Mode

Step-Down Mode

× 2mm) DFN Package

3.3V/2.5V Step-Up/

Step-Down Charge Pump

DC/DC Converter

charge pump DC/DC converters that produce a fixed

regulated output voltage of 3.3V or 2.5V over a wide input

voltage range (1.8V to 5.5V).

With input voltages greater than the regulated output

voltage the LTC3240 operates as a low dropout regulator.

Once the input voltage drops within 100mV of the regulated

output voltage the part automatically switches to step-up

mode. In step-up mode the LTC3240 operates as a constant

frequency (1.2MHz) doubling charge pump.

The LTC3240-3.3/LTC3240-2.5 feature low no load operat-

ing current (65µA typical) and ultralow operating current

in shutdown (<1µA). Built-in soft-start circuitry prevents

excessive inrush current during start-up. Thermal shut-

down and current-limit circuitry allow the parts to survive

The LTC3240-3.3/LTC3240-2.5 require only three tiny

external ceramic capacitors for an ultrasmall application

footprint. The LTC3240-3.3/LTC3240-2.5 are available in a

6-pin (2mm

× 2mm) DFN package.

Audio, PC Cards, Misc. Logic, etc., in a Wide Variety

of Handheld Products

Output Voltage vs Input Voltage (Full Range)

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

OFF ON

GND

SHDN

LTC3240-3.3

1

µF

4.7

µF

1

µF

3.3V

2.7V TO 4.5V

3240 TA01a

Li-Ion OR

3-CELL NiMH

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

All other trademarks are the property of their respective owners.

Protected by U.S. Patents including 6411531.

Li-Ion to 3.3V at Up to 150mA

INPUT VOLTAGE (V)

1.7

3.30

3.40

5.7

3240 TA01b

3.20

3.10

2.7

3.7

4.7

2.2

3.2

4.2

5.2

3.50

3.25

3.35

3.15

3.45