LTC3521 LINER [Linear Technology], LTC3521 Datasheet - Page 3

• Manufacturer Part Number: LTC3521
• Description: Wide VIN, 1A Buck-Boost DC/DC and Dual 600mA Buck DC/DC Converters
• Manufacturer: LINER [Linear Technology]

elecTrical characTerisTics
PARAMETER
Oscillator Frequency
SHDN1, SHDN2, SHDN3, PWM Input High Voltage
SHDN1, SHDN2, SHDN3, PWM Input Low Voltage
Power Good Outputs Low Voltage
Power Good Outputs Leakage Current
Buck Converters
PMOS Switch Resistance
NMOS Switch Resistance
NMOS Switch Leakage Current
PMOS Switch Leakage Current
Feedback Voltage
Feedback Input Current
PMOS Current Limit
Maximum Duty Cycle
Minimum Duty Cycle
PGOOD Threshold
Power Good Hysteresis
Buck-Boost Converter
Output Voltage
PMOS Switch Resistance
NMOS Switch Resistance
NMOS Switch Leakage Current
PMOS Switch Leakage Current
Feedback Voltage
Feedback Input Current
Average Current Limit
Reverse Current Limit
Maximum Duty Cycle
Minimum Duty Cycle
PGOOD Threshold
Power Good Hysteresis
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 LTC3521 is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 85°C operating
junction temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 3: Current measurements are performed when the LTC3521 is not
switching. The current limit values in operation will be somewhat higher
due to the propagation delay of the comparators.
junction temperature range, otherwise specifications are at T
CONDITIONS
I
V
V
V
(Note 4)
V
(Note 3)
V
V
V
V
V
V
(Note 4)
V
(Note 3)
(Note 3)
V
V
V
V
PGOOD1
PGOOD1
SW2
SW2
FB2
FB2
FB2
FB2,3
FB2,3
SW1A
SW1A
FB1
FB1
FB1
FB1
FB1
= V
= V
= V
= 0.6V
= 0.55V
= 0.66V
Falling
Returning Good
= V
= V
Falling
Returning Good
= V
= V
= I
FB3
FB3
FB3
= V
SW3
SW3
SW1B
SW1B
PGOOD2
= 0.6V
= 0.55V
= 0.66V
PGOOD2
= 5.5V, V
= 0V, V
The
= 5.5V, V
= 0V, V
J
= I
= 25°C. V
= V
l
IN
PGOOD3
IN
IN
= 5.5V
denotes the specifications which apply over the full operating
PGOOD3
IN
= 5.5V
= 5.5V
= 5.5V
Note 4: The LTC3521 is tested in a proprietary test mode that connects
each FB pin to the output of the respective error amplifier.
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 impair device reliability.
= 1mA
IN
= 5.5V
= 3.6V, V
OUT1
= 3.3V, unless otherwise noted.
l
l
l
l
l
l
l
l
l
l
l
l
0.585
0.585
0.85
1.65
MIN
750
100
–12
–12
1.4
1.8
85
0.205
0.170
0.110
0.085
1050
TYP
375
1.1
0.1
0.1
0.1
0.1
0.6
0.1
0.1
0.6
2.1
–9
94
–9
1
2
1
3
LTC3521
0.612
0.612
MAX
1.35
5.25
0.4
0.2
10
10
50
–6
10
50
–6
5
0
5
0
UNITS

MHz
3521f
mA
mA
µA
µA
µA
nA
µA
µA
nA
%
%
%
%
%
%
%
%
Ω
Ω
Ω
Ω
V
V
V
V
V
V
A