LTC3125_15 Datasheet, PDF (18/18 Pages) Linear Technology – 1.2A Synchronous Step-Up DC/DC Converter with Input Current Limit

LTC3125
TYPICAL APPLICATION
PC Card or CompactFlash (3.3V/500mA Maximum) 4.5V Output,
GSM Pulsed Load
2.2μH*
V_IN
PC CARD V_CC
3.3V ±10%
500mA MAX
10μF
CER
CS
SW
V_IN
V_OUT
LTC3125
OFF ON
44.2k
SHDN
PROG
FB
GND
V_OUT
4.5V, 2A PULSED LOAD
(577μs PW, 4.6ms PERIOD)
2.74M
2200μF**
×2
55mΩ
TANT
1M
3125 TA02a
*COILTRONICS SD3118-2R2-R
**VISHAY 592D228X6R3X220H
Waveforms of Input Current, V_OUT for Pulsed Load Current
V_OUT
100mV/DIV
INPUT CURRENT
200mA/DIV
LOAD CURRENT
2A/DIV
V_IN = 3.3V
V_OUT = 4.5V
C_OUT = 4.4mF
L = 2.2μH
R_PROG = 44.2k
1ms/DIV
3125 TA02b
RELATED PARTS
PART NUMBER
LTC3127
LTC3421
LTC3422
LTC3459
DESCRIPTION
1A Buck-Boost Converter with Programmable Input Current
Limit
3A (I_SW), 3MHz, Synchronous Step-Up DC/DC Converter with
Output Disconnect
1.5A (I_SW), 3MHz Synchronous Step-Up DC/DC Converter with
Output Disconnect
80mA (I_SW), Synchronous Step-Up DC/DC Converter
LTC3523/LTC3523-2 600mA (I_SW), Step-Up and 400MHz Synchronous Step-Down
1.2MHz/2.4MHz DC/DC Converter with Output Disconnect
LTC3525-3/
LTC3525-3.3/
LTC3525-5
400mA (I_SW), Micropower Synchronous Step-Up DC/DC
Converter with Output Disconnect
LTC3526/LTC3526L 500mA (I_SW), 1MHz Synchronous Step-Up DC/DC Converter
LTC3526B
with Output Disconnect
LTC3527/LTC3527-1 Dual 800mA/400mA (I_SW), 2.2MHz Synchronous Step-Up
DC/DC Converter with Output Disconnect
LTC3528/LTC3528B 1A (I_SW), 1MHz Synchronous Step-Up DC/DC Converter with
Output Disconnect
LTC3537
600mA (I_SW), 2.2MHz Synchronous Step-Up DC/DC Converter
with Output Disconnect and 100mA LDO
LTC3539/LTC3539-2 2A (I_SW), 1MHz, 2.2MHz Synchronous Step-Up DC/DC
Converter with Output Disconnect
COMMENTS
96% Efficiency, ±4% Accurate Average Input Current Limit,
V_IN: 1.8V to 5.5V, V_OUT = 1.8V to 5.25V, I_Q = 35μA, DFN Package
94% Efficiency, V_IN: 0.85V to 4.5V, V_OUT(MAX) = 5.25V,
I_Q = 12μA, I_SD < 1μA, 4mm × 4mm QFN24 Package
94% Efficiency, V_IN: 0.85V to 4.5V, V_OUT(MAX) = 5.25V,
I_Q = 25μA, I_SD < 1μA, 3mm × 3mm DFN10 Package
92% Efficiency, V_IN: 1.5V to 5.5V, V_OUT(MAX) = 10V, I_Q = 10μA,
I_SD < 1μA, ThinSOT Package
94% Efficiency V_IN: 1.8V to 5.5V, V_OUT(MAX) = 5.25V, I_Q = 45μA,
I_SD < 1μA, 3mm × 3mm QFN16 Package
94% Efficiency, V_IN: 0.85V to 4V, V_OUT(MAX) = 5V, I_Q = 7μA,
I_SD < 1μA, SC-70 Package
94% Efficiency V_IN: 0.85V to 5V, V_OUT(MAX) = 5.25V, I_Q = 9μA, I_SD
< 1μA, 2mm × 2mm DFN6 Package
94% Efficiency V_IN: 0.7V to 5V, V_OUT(MAX) = 5.25V, I_Q = 12μA, I_SD
< 1μA, 3mm × 3mm QFN16 Package
94% Efficiency V_IN: 0.7V to 5.5V, V_OUT(MAX) = 5.25V, I_Q = 12μA,
I_SD < 1μA, 2mm × 3mm DFN8 Package
94% Efficiency V_IN: 0.7V to 5V, V_OUT(MAX) = 5.25V, I_Q = 30μA,
I_SD < 1μA, 3mm × 3mm QFN16 Package
94% Efficiency, V_IN: 0.7V to 5V, V_OUT(MAX) = 5.25V,
I_Q = 10μA, I_SD < 1μA, 2mm × 3mm DFN Package
18 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
3125fa
LT 1210 REV A • PRINTED IN USA
© LINEAR TECHNOLOGY CORPORATION 2008