Datasheet

LT3990
4
3990f
Typical perFormance characTerisTics
No-Load Supply Current No-Load Supply Current Maximum Load Current
Maximum Load Current Maximum Load Current Load Regulation
Efficiency, V
OUT
= 3.3V Efficiency, V
OUT
= 5V V
FB
vs Temperature
T
A
= 25°C, unless otherwise noted.
INPUT VOLTAGE (V)
1.0
SUPPLY CURRENT (µA)
1.5
2.0
2.5
3.0
15 35
55
3990 G04
3.5
4.0
5 25
45
FRONT PAGE APPLICATION
V
OUT
= 3.3V
R1 = 1M
R2 = 576k
TEMPERATURE (°C)
–50
SUPPLY CURRENT (µA)
9
12
15
25 75 150
3990 G05
6
3
0
–25 0
50
100 125
FRONT PAGE APPLICATION
V
IN
= 12V
V
OUT
= 3.3V
R1 = 1M
R2 = 576k
INPUT VOLTAGE (V)
5
350
LOAD CURRENT (mA)
400
450
500
650
600
550
15 25 35 45
3990 G06
55
FRONT PAGE APPLICATION
V
OUT
= 3.3V
TYPICAL
MINIMUM
INPUT VOLTAGE (V)
5
350
LOAD CURRENT (mA)
400
450
500
650
600
550
15 25 35 45
3990 G07
55
FRONT PAGE APPLICATION
V
OUT
= 5V
TYPICAL
MINIMUM
TEMPERATURE (°C)
–50
LOAD CURRENT (mA)
300
400
500
600
25 75
3990 G08
200
100
0
–25 0
50
100 125
FRONT PAGE APPLICATION
V
IN
= 12V
V
OUT
= 5V
LIMITED BY MAXIMUM
JUNCTION TEMPERATURE;
Q
JA
= 45°C/W
LIMITED BY CURRENT LIMIT
LOAD CURRENT (mA)
0
LOAD REGULATION (%)
0.15
150
3990 G09
0
–0.10
50 100 200
–0.15
–0.20
0.25
0.20
0.10
0.05
–0.05
250 300 350
FRONT PAGE APPLICATION
REFERENCED FROM V
OUT
AT 100mA LOAD
LOAD CURRENT (mA)
50
EFFICIENCY (%)
60
70
80
90
0.01 101 100
3990 G01
10
20
40
30
0.1
V
IN
= 12V
V
IN
= 48V
FRONT PAGE APPLICATION
V
OUT
= 3.3V
R1 = 1M
R2 = 576k
V
IN
= 24V
V
IN
= 36V
LOAD CURRENT (mA)
50
EFFICIENCY (%)
60
70
80
90
0.01 101 100
3990 G02
20
40
30
0.1
V
IN
= 12V
V
IN
= 48V
FRONT PAGE APPLICATION
V
IN
= 36V
V
IN
= 24V
TEMPERATURE (°C)
–50
V
FB
(V)
1.210
1.215
1.220
25 75 150
3990 G03
1.205
1.200
1.195
–25 0
50
100 125