LTC3406-1.2 Datasheet, PDF (1/12 Pages) Linear Technology – 1.5MHz, 600mA Synchronous Step-Down Regulator in ThinSOT

FEATURES
■ _{High Efficiency: Up to 90%}
■ _{Very Low Quiescent Current: Only 20µA}
■ _{600mA Output Current at VIN = 3V}
■ _{2.5V to 5.5V Input Voltage Range}
■ _{1.5MHz Constant Frequency Operation}
■ _{No Schottky Diode Required}
■ _{Shutdown Mode Draws < 1µA Supply Current}
■ _{Current Mode Operation for Excellent Line and}
Load Transient Response
■ _{Overtemperature Protected}
■ _{Low Profile (1mm) ThinSOT}^TM _Package
U
APPLICATIO S
■ _{Cellular Telephones}
■ _{Personal Information Appliances}
■ _{Wireless and DSL Modems}
■ _{Digital Still Cameras}
■ _{MP3 Players}
■ _{Portable Instruments}
LTC3406-1.2
1.5MHz, 600mA
Synchronous Step-Down
Regulator in ThinSOT
DESCRIPTIO
The LTC^®3406-1.2 is a high efficiency monolithic syn-
chronous buck regulator using a constant frequency,
current mode architecture. Supply current during opera-
tion with only 20µA drops <1µA in shutdown. The 2.5V to
5.5V input voltage range makes the LTC3406-1.2 ideally
suited for single Li-Ion battery-powered applications. 100%
duty cycle provides low dropout operation, extending
battery life in portable systems. PWM pulse skipping
mode operation provides very low output ripple voltage for
noise sensitive applications.
Switching frequency is internally set at 1.5MHz, allowing
the use of small surface mount inductors and capacitors.
The internal synchronous switch increases efficiency and
eliminates the need for an external Schottky diode. The
LTC3406-1.2 is available in a low profile (1mm) ThinSOT
package.
, LTC and LT are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners. ThinSOT is a trademark of Linear
Technology Corporation. Protected by U.S. Patents including 5481178, 6580258, 6304066,
6127815, 6498466, 6611131.
TYPICAL APPLICATIO
V_IN
2.7V TO 5.5V
High Efficiency Step-Down Converter
C_IN
4.7µF
CER
V_IN
SW
LTC3406-1.2
RUN V_OUT
GND
2.2µH
340612 TA01a
C_OUT
10µF
CER
V_OUT
1.2V
600mA
Efficiency and Power Loss
100
1
90
EFFICIENCY
80
0.1
70
60
0.01
50
POWER LOSS
40
0.001
30
20
10
0
0.1
V_IN = 2.7V ^0.0001
V_IN = 3.6V
V_IN = 4.2V _0.00001
1
10
100
1000
LOAD CURRENT (mA)
340612 TA01b
340612f
1