LT3970 Series
4
3970fc
Typical perFormance characTerisTics
Efficiency, V
OUT
= 3.3V Efficiency, V
OUT
= 5V LT3970 Feedback Voltage
T
A
= 25°C, unless otherwise noted.
LOAD CURRENT (mA)
50
EFFICIENCY (%)
70
90
40
60
80
0.01 1 10 100
30
20
0.1
V
IN
= 12V
FRONT PAGE APPLICATION
V
OUT
= 3.3V
R1 = 1M
R2 = 576k
V
IN
= 36V
V
IN
= 24V
LOAD CURRENT (mA)
50
EFFICIENCY (%)
70
90
40
60
80
0.01 1 10 100
30
0.1
V
IN
= 12V
FRONT PAGE APPLICATION
V
IN
= 36V
V
IN
= 24V
TEMPERATURE (°C)
–50
FEEDBACK VOLTAGE (V)
1.210
1.215
1.220
25 75 150
1.205
1.200
1.195
–25 0
50
100 125
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 LT3970E 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
LT3970I is guaranteed over the full –40°C to 125°C operating junction
temperature range. The LT3970H is guaranteed over the full –40°C to
150°C operating junction temperature range. High junction temperatures
degrade operating lifetimes. Operating lifetime is derated at junction
temperatures greater than 125°C.
Note 3: Bias current flows into the FB pin.
Note 4: This is the minimum voltage across the boost capacitor needed to
guarantee full saturation of the switch.
LT3970-5 Output VoltageLT3970-3.3 Output Voltage LT3970-3.42 Output Voltage
TEMPERATURE (°C)
–50
OUTPUT VOLTAGE (V)
3.30
3.31
3.32
25 75 150
3970 G04
3.29
3.28
3.27
–25 0
50
100 125
TEMPERATURE (°C)
–50
OUTPUT VOLTAGE (V)
3.42
3.43
3.44
25 75 125
3970 G05
3.41
3.40
3.39
–25 0
50
100
TEMPERATURE (°C)
–50
OUTPUT VOLTAGE (V)
5.00
5.02
5.04
25 75 150
3970 G06
4.98
4.96
4.94
–25 0
50
100 125