LT3479
3
3479fc
ELECTRICAL CHARACTERISTICS
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 LT3479 is guaranteed to meet performance specifi cations
from 0°C to 70°C. Specifi cations over the –40°C to 85°C operating
PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage
l
2.3 2.5 V
Quiescent Current V
IN
= 2.5V, V
SHDN
= 0V
V
IN
= 2.5V, V
SHDN
= 2.5V, V
C
= 0.3V (Not Switching)
0.1
5
1
7.5
μA
mA
Reference Voltage Measured at V
REF
Pin
l
1.216 1.235 1.250 V
Reference Voltage Line Regulation 2.5V < V
IN
< 24V, V
C
= 0.3V 0.01 0.03 %/V
Maximum V
REF
Pin Current Out of Pin 100 μA
Soft-Start Pin Current SS = 0.5V, Out of Pin 9 μA
FBP Pin Bias Current 25 100 nA
FBN Pin Bias Current 25 100 nA
Feedback Amplifi er Offset Voltage FBP – FBN, V
C
= 1V –2 2 6 mV
Feedback Amplifi er Voltage Gain 250 V/V
Feedback Amplifi er Transconductance 150 μS
Feedback Amplifi er Sink Current V
FBP
= 1.25V, V
FBN
= 1.5V, V
C
= 0.5V 10 μA
Feedback Amplifi er Source Current V
FBP
= 1.25V, V
FBN
= 1V, V
C
= 0.5V 10 μA
Switching Frequency R
T
= 17.8k
R
T
= 113k
R
T
= 1.78k
0.9
160
2.7
1
200
3.5
1.15
240
4.1
MHz
kHz
MHz
Maximum Switch Duty Cycle R
T
= 17.8k
l
84 93 %
SHDN Pin Current V
SHDN
= 5V
V
SHDN
= 0V
30
0.1
60
1
μA
μA
SHDN Pin Threshold 0.3 1.5 2 V
Inductor Current Limit (Note 3) 3.5 5 6.5 A
Switch Current Limit (Note 3) 3 4.5 6 A
Switch V
CESAT
I
SW
= 1A (Note 3) 120 200 mV
Switch Leakage Current SW = 40V 0.2 5 μA
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
IN
= 2.5V, V
SHDN
= 2.5V.
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 3: Inductor Current Limit, Switch Current Limit and Switch V
CESAT
for
DE package guaranteed by design and/or correlation to static test.
