LTC3459
10V Micropower
Synchronous Boost Converter
FEATURES
DESCRIPTION
TheLTC®3459isalowcurrent,highefficiencysynchronous
boost converter intended for low power, size constrained
portable applications. The LTC3459 can be powered from
a single lithium ion battery, a 2- to 3-cell stack of alkaline
or nickel batteries, or any low impedance voltage source
between 1.5V and 5.5V. The output is programmable via
an external divider between 2.5V and 10V. Although the
n
Small Solution Size
n
>85% Efficiency over Wide Load Range
n
Internal Synchronous Rectifier
n
V Range: 1.5V to 5.5V
IN
n
5V at 30mA from 3.3V Input
n
3.3V at 20mA from 2 AA Cell Input
n
Programmable Output Voltages Up to 10V
Burst Mode® Operation
n
part is primarily intended for boost applications, V
maintain regulation below V (at reduced efficiency).
will
OUT
n
Inrush Current Limiting
Output Disconnect in Shutdown
IN
n
The LTC3459 offers Burst Mode operation with a fixed
peak current, providing high conversion efficiency over
a wide range of load currents. During start-up, inductor
current is controlled preventing the inrush surge current
found in many boost converters. In shutdown the output
is disconnected from the input and quiescent current is
reduced to <1μA.
n
Ultralow Quiescent (10μA) and Shutdown (<1μA)
Currents
n
Low Profile 2mm × 2mm DFN, 2mm × 3mm DFN or
SOT-23 Package
APPLICATIONS
The LTC3459 is offered in low profile 6-pin 2mm × 2mm
DFN, 2mm × 3mm DFN or SOT-23 (ThinSOTTM) packages,
allowing a tiny footprint for the total solution.
, LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology
Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
n
General Purpose Micropower Boost
n
Digital Cameras
n
PDAs
LCD Bias
Small OLED Displays
Supercap Charging
n
n
n
TYPICAL APPLICATION
5V to 8V Converter
Efficiency
100
V
V
= 5V
IN
OUT
= 8V
22μH
90
80
70
60
50
SW
V
OUT
8V
5V
V
V
OUT
IN
30mA
2M
47pF
LTC3459
OFF ON
SHDN
GND
FB
1μF
4.7μF
365k
3459 TA01a
0.01
0.1
1
10
100
I
(mA)
LOAD
3459 TA01b
3459fc
1