Datasheet
LTC3535
3
3535fa
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3535 is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 3: Specification is guaranteed by design and not 100% tested in
production.
(For each channel) The l denotes the specifications which apply over the specified
operating temperature range of –40°C to 85°C, otherwise specifications are at T
A
= 25°C. V
IN
= 1.2V, V
OUT
= 3.3V unless otherwise noted.
ELECTRICAL CHARACTERISTICS
PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Duty Cycle V
FB
= 1.3V
l
0 %
Switching Frequency
l
0.75 1 1.25 MHz
SHDN Pin Input High Voltage 0.8 V
SHDN Pin Input Low Voltage 0.3 V
Note 4: Current measurements are made when the output is not switching.
Note 5: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may result in device degradation or failure.
Note 6: Failure to solder the exposed backside of the package to the PC
board ground plane will result in a thermal resistance much higher than
43°C/W.
TYPICAL PERFORMANCE CHARACTERISTICS
(Each Channel) T
A
= 25°C, unless otherwise noted.
Efficiency vs Load Current
and V
IN
for V
OUT
= 1.8V
Efficiency vs Load Current
and V
IN
for V
OUT
= 3.3V
No-Load Input Current vs V
IN
LOAD CURRENT (mA)
0.01
40
EFFICIENCY (%)
POWER LOSS (mW)
50
60
70
80
0.1 1 10 100 1000
3535 G01
30
20
10
0
90
100
1
10
100
0.1
0.01
1000
V
IN
= 1.0V
V
IN
= 1.2V
V
IN
= 1.5V
POWER LOSS
EFFICIENCY
LOAD CURRENT (mA)
0.01
40
EFFICIENCY (%)
POWER LOSS (mW)
50
60
70
80
0.1 1 10 100 1000
3535 G02
30
20
10
0
90
100
1
10
100
0.1
0.01
1000
V
IN
= 1.2V
V
IN
= 1.8V
V
IN
= 2.4V
V
IN
= 3.0V
POWER LOSS
EFFICIENCY
V
IN
(V)
0.5
I
IN
(µA)
60
70
80
4.5
3535 G04
50
40
10
1.5
2.5
3.5
1.0
2.0
3.0
4.0
30
20
100
90
V
OUT
= 3.3V
V
OUT
= 5V
V
OUT
= 2.5V
V
OUT
= 1.8V