Datasheet

LT3579/LT3579-1
4
35791fa
For more information www.linear.com/LT3579
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 LT3579E is guaranteed to meet performance specifications
from 0°C to 125°C junction temperature. Specifications over the –40°C
to 125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LT3579I is guaranteed over the full –40°C to 125°C operating junction
temperature range.
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 5V, V
SHDN
= V
IN
, V
FAULT
= V
IN
unless otherwise noted. (Note 2).
PARAMETER CONDITIONS MIN TYP MAX UNITS
Soft-Start Charge Current V
SS
= 30mV, Current Flows Out of SS pin
l
5.7 8.7 11.3 µA
Soft-Start Discharge Current Part in FAULT
V
SS
= 2.1V,
Current Flows into SS Pin
l
5.7 8.7 11.3 µA
Soft-Start High Detection Voltage Part in F
AULT
l
1.65 1.8 1.95 V
Soft-Start Low Detection Voltage Part Exiting FAULT
l
30 50 85 mV
SHDN Minimum Input Voltage High Active Mode, SHDN Rising
Active Mode, SHDN Falling
l
l
1.27
1.24
1.33
1.3
1.41
1.38
V
V
SHDN Input V
oltage Low Shutdown Mode
l
.3 V
SHDN Pin Bias Current V
SHDN
= 3V
V
SHDN
= 1.3V
V
SHDN
= 0V
9.5
40
11.4
0
60
13.4
0.1
µA
µA
µA
CLKOUT Output Voltage High C
CLKOUT
= 50pF 1.9 2.1 2.3 V
CLKOUT Output Voltage Low C
CLKOUT
= 50pF 100 200 mV
CLKOUT Duty Cycle LT3579, T
J
= 25°C 42 %
LT3579-1, All T
J
50 %
CLKOUT Rise Time C
CLKOUT
= 50pF 12 ns
CLKOUT Fall Time C
CLKOUT
= 50pF 8 ns
GATE Pull Down Current V
GATE
= 3V
V
GATE
= 80V
l
l
800
800
933
933
1100
1100
µA
µA
GATE Leakage Current V
GATE
= 50V, GATE Off 0.01 1 µA
FAULT Output Voltage Low 50μA into FAULT Pin
l
100 300 mV
FAULT Leakage Current V
FAULT
= 40V, FAULT Off 0.01 1 µA
FAULT Input Voltage Low Threshold
l
700 750 800 mV
FAULT Input Voltage High Threshold
l
950 1000 1050 mV
Note 3: Current limit guaranteed by design and/or correlation to static test.
Note 4: 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 over the specified maximum operating junction
temperature may impair device reliability.