LTC3525L-3_15 Datasheet, PDF (1/12 Pages) Linear Technology – 400mA Micropower Synchronous Step-Up DC/DC Converter with Output Disconnect

LTC3525L-3
400mA Micropower
Synchronous Step-Up DC/DC
Converter with Output Disconnect
FEATURES
n _{Start-Up at 0.7V Typical, 0.88V Guaranteed}
n _{Up to 95% Efficiency}
n _{Output Disconnect and Inrush Current Limit}
n _{3V Fixed Output Voltage}
n _{Delivers 65mA at 3V from a 1V Input or 160mA}
from a 1.8V Input
n _{Burst Mode}^® _{Operation: IQ = 7µA}
n _{VIN: 0.5V to 4.5V}
n _{Only Three External Components}
n _{VIN > VOUT Operation}
n _{<1µA Shutdown Current}
n _{Anti-Ringing Control}
n _{Short-Circuit and Overtemperature Protection}
n _{Tiny 6-Pin SC70 Package}
APPLICATIONS
n _{MP3 Players}
n _{Portable Instruments}
n _{Glucose Meters}
n _{Digital Cameras}
DESCRIPTION
The LTC^®3525L-3 is a high efficiency synchronous step-
up DC/DC converter with output disconnect that can
start up with an input as low as 0.7V. It offers a compact,
high efficiency alternative to charge pumps in single
cell or dual cell alkaline applications. Only three small
external components are required. The LTC3525L-3
generates a fixed 3V output voltage.
The device includes a 0.5 N-channel MOSFET switch
and a 0.85 P-channel synchronous rectifier. Peak switch
current ranges from 150mA to 400mA, depending on
load, providing enhanced efficiency. Quiescent current
is an ultralow 7µA, maximizing battery life in portable
applications.
Other features include <1µA shutdown current, anti-
ringing control and thermal shutdown. The LTC3525L-3
is available in a tiny 6-pin SC70 package.
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners. Patents pending.
TYPICAL APPLICATION
L1*
10µH
V_IN
0.9V TO 1.6V
OFF ON
1µF
LTC3525L-3
V_IN
SW
SHDN
V_OUT
GND
GND
V_OUT
3V
65mA
10µF
*MURATA LQH32CN100K53
3525 TA01
LTC3525L-3 Efficiency and Power
Loss vs Load Current
100
100
90
80
10
EFFICIENCY
70
60
1
POWER LOSS
50
40
0.1
30
20
0.01 0.1
1
10
LOAD (mA)
V_IN = 2.4V
V_IN = 1.2V
0.01
100 1000
LT3525 • TA02
3525lfa
1