LTC3530

1

3530fb

Wide Input Voltage

Synchronous Buck-Boost

DC/DC Converter

frequency, buck-boost DC/DC converter that operates

from input voltages above, below or equal to the output

voltage. The topology incorporated in the IC provides a

continuous transfer function through all operating modes,

making the product ideal for single lithium-ion, two-cell

alkaline or NiMH applications where the output voltage is

within the battery voltage range.

The LTC3530 is pin compatible with the LTC3440 buck-

boost DC/DC converter but adds programmable automatic

1.8V. Switching frequencies up to 2MHz are programmed

with an external resistor. Automatic Burst Mode operation

allows the user to program the load current threshold for

Burst Mode operation using a single resistor from the

BURST pin to GND.

Other features include 1μA shutdown, short circuit pro-

tection, programmable soft-start control, current limit

and thermal shutdown. The LTC3530 is available in a

thermally enhanced 10-lead (3mm × 3mm) DFN or MSOP

package.

or Equal to the Output

Li-Ion

DFN and 10-Lead MS Packages

Efficiency

SW1

SHDN/SS

SW2

FB

BURST

LTC3530

10μF

1.8V TO 5.5V

1M

22μF

3.3V AT

250mA

576k

0.01μF

10k

560pF

3530 TA01a

4.7μH

33.2k

100k

GND

ON

OFF

33pF

15k

LOAD CURRENT (mA)

30

90

100

20

10

80

50

70

60

40

0.1

10

100

1000

3350 TA01b

0

1

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

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

All other trademarks are the property of their respective owners. Patents Pending.