LTC3125_15 Datasheet, PDF (13/18 Pages) Linear Technology – 1.2A Synchronous Step-Up DC/DC Converter with Input Current Limit

LTC3125
TYPICAL APPLICATIONS
PC Card (3.3V/1000mA Maximum) 4.5V Output, GPRS, Class 10 Pulsed Load
2.7μH*
V_IN
PC CARD V_CC
3.3V ±10%
1000mA MAX
10μF
CER
OFF ON
CS
SW
V_IN
V_OUT
LTC3125
SHDN
2.74M
22.6k
PROG
FB
GND
1M
3125 TA04a
*WURTH 7440420027
**VISHAY 592D228X6R3X220H
V_OUT
4.5V, 2A PULSED LOAD
(1154μs PW, 4.6ms PERIOD)
2200μF**
s3
55mΩ
TANT
Waveforms of Input Current,
V_OUT for Pulsed Load Current
V_OUT
100mV/DIV
INPUT CURRENT
500mA/DIV
LOAD CURRENT
2A/DIV
V_IN = 3.3V
V_OUT = 4.5V
C_OUT = 6.6mF
L = 2.7μH
R_PROG = 22.6k
1ms/DIV
3125 TA04b
V_IN
3.3V ±10%
1000mA MAX
Single Supercap Charger
2.2μH*
10μF
CER
OFF ON
22.6k
CS
SW
V_IN
V_OUT
LTC3125
SHDN
1.07M
V_OUT
2.5V
SC**
10F
60mΩ
PROG
FB
GND
1M
3125 TA05a
*COILTRONICS SD3118-2R2-R
**COOPER B1325-2R5106-R
Waveforms of Input Current,
V_OUT for Pulsed Load Current
V_OUT
500mV/DIV
INPUT CURRENT
500mA/DIV
LOAD CURRENT
1A/DIV
V_IN = 3.3V
V_OUT = 2.5V
C_OUT = 10F
L = 2.2μH
R_PROG = 22.6k
200ms/DIV
3125 TA05b
3125fa
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