LTC3125 Linear Technology, LTC3125 Datasheet - Page 14

• Manufacturer Part Number: LTC3125
• Description: 1.2A Synchronous Step-Up DC/DC Converter
• Manufacturer: Linear Technology

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LTC3125
TYPICAL APPLICATIONS
14
Waveforms of Input Current, V
500mA MAX
2.5V TO 5V
INPUT CURRENT
LOAD CURRENT
M1 GATE DRIVE
3.3V ±10%
300mA 500mA
200mA/DIV
200mA/DIV
V
Waveforms of Input Current, V
IN
2V/DIV
5V/DIV
V
5V/DIV
3.3V to 5V with Selectable Input Current Limit
SHDN
IN
V
OUT
V
V
C
L = 2.2μH
R
V
V
C
L = 2.2μH
I
LOAD
IN
OUT
OUT_SERIES
10μF
CER
PROG
IN
OUT
OUT
= 4.5V
= 3.3V
10μF
CER
= 4.5V
OFF ON
= 5V
= 4.4mF
= 500mA
= 44.2k
44.2k
Stacked Supercap Charger
M1
OFF ON
= 15F
44.2k
28.7k
V
SHDN
PROG
CS
IN
20s/DIV
V
SHDN
PROG
2ms/DIV
LTC3125
CS
OUT
2.2μH*
IN
GND
LTC3125
2.2μH*
GND
for Pulsed Input Current Limit
*TDK VLF4014ST-2R2M1R9
**PANASONIC EECHWOD306
V
SW
OUT
FB
OUT
*TDK VLF4014ST-2R2M1R9
V
SW
OUT
FB
During Charging
2.74M
1M
3125 TA07a
3.2M
1M
3125 TA06b
3125 TA07b
100k
100k
3125 TA06a
C
+
+
OUT
V
5V
OUT
V
4.5V
30F**
2.3V
30F**
2.3V
OUT
3125f