LTC3400-1
600mA, 1.2MHz Micropower
Synchronous Boost Converter
in ThinSOT
FEATURES
■
■
■
■
■
■
■
■
■
■
■
DESCRIPTIO
Up to 92% Efficiency
Generates 3.3V at 100mA from a Single AA Cell
Low Start-Up Voltage: 0.85V
V
OUT
Connected to V
IN
in Shutdown
Internal Synchronous Rectifier
2.5V to 5V Output Range
Automatic Burst Mode
®
Operation
Logic Controlled Shutdown (< 1µA)
Antiringing Control Minimizes EMI
Tiny External Components
Low Profile (1mm) SOT-23 Package
The LTC
®
3400-1 is a synchronous, fixed frequency, step-
up DC/DC converter delivering high efficiency in a 6-lead
ThinSOT™ package. Capable of supplying 3.3V at 100mA
from a single AA cell input, the device contains an internal
NMOS switch and PMOS synchronous rectifier.
A switching frequency of 1.2MHz minimizes solution
footprint by allowing the use of tiny, low profile inductors
and ceramic capacitors. The current mode PWM design is
internally compensated, reducing external parts count.
The LTC3400-1 features automatic shifting to power sav-
ing Burst Mode operation at light loads. In shutdown, V
OUT
and V
IN
are connected, which allows the input battery to be
used for backup power. The LTC3400-1 features low
shutdown current of under 1µA.
The LTC3400-1 is offered in the low profile (1mm)
SOT-23 package.
, LTC, LT and Burst Mode are registered trademarks of Linear Technology Corporation.
ThinSOT is a trademark of Linear Technology Corporation.
US Patent Numbers 5,481,178; 6,580,258; 6,304,066; 6,127,815; 6,498,466; 6,611,131.
APPLICATIO S
■
■
■
■
■
■
■
Pagers
MP3 Players
Digital Cameras
LCD Bias Supplies
Handheld Instruments
Wireless Handsets
GPS Receivers
TYPICAL APPLICATIO
100
Single Cell to 3.3V Synchronous Boost Converter
90
4.7µH
SINGLE
AA CELL
4.7µF
V
IN
EFFICIENCY (%)
+
80
70
60
50
SW
V
OUT
1.02M
1%
604k
1%
LTC3400-1
OFF ON
SHDN
GND
FB
V
OUT
3.3V
100mA
4.7µF
FIGURE 1 CIRCUIT
WITH OPTIONAL SCHOTTKY DIODE
(SEE APPLICATIONS INFORMATION)
1
10
100
LOAD CURRENT (mA)
1000
34001 F01a
34001 F01
40
0.1
U
Efficiency
V
IN
= 2.4V
V
IN
= 1.5V
34001f
U
U
1
LINER [ LINEAR TECHNOLOGY ]
