Datasheet

LT3980
4
3980fa
For more information www.linear.com/LT3980
INPUT VOLTAGE (V)
0
SUPPLY CURRENT (µA)
3980 G04
50
30
10 20
10
130
110
90
70
30 40 50 60
V
OUT
= 3.3V
DUTY CYCLE (%)
0
SWITCH CURRENT LIMIT (A)
40
3980 G08
3.5
20 60
2.5
2.0
5.0
4.5
4.0
3.0
80 100
TYPICAL
MINIMUM
TEMPERATURE (°C)
–50
SUPPLY CURRENT (µA)
350
25
3980 G05
200
100
–25 0 50
50
0
400
300
250
150
75 100 150125
V
IN
= 12V
V
OUT
= 3.3V
CATCH DIODE: DIODES, INC. PDS360
INCREASED SUPPLY
CURRENT DUE TO CATCH
DIODE LEAKAGE AT
HIGH TEMPERATURE
I
LOAD
(A)
0 0.5
EFFICIENCY (%)
1
2
3980 G02
1.5
V
IN
= 12V
V
IN
= 48V
f = 400kHz
D = DIODES, INC. SBR3U100LP
V
IN
= 24V
85
70
60
55
50
95
90
80
75
65
INPUT VOLTAGE (V)
LOAD CURRENT (A)
3980 G07
2.0
3.5
3.0
2.5
TYPICAL
MINIMUM
5 10 20 30 40 5015 25 35 45 6055
INPUT VOLTAGE (V)
LOAD CURRENT (A)
3980 G06
2.0
3.5
3.0
2.5
TYPICAL
MINIMUM
5 10 20 30 40 5015 25 35 45 6055
TEMPERATURE (°C)
SWITCH CURRENT LIMIT (A)
4.0
4.5
5.5
5.0
3980 G09
3.5
3.0
2.0
2.5
6.5
6.0
DUTY CYCLE = 10%
–50 25–25 0 50 75 100 150125
Efficiency, V
OUT
= 5V
No-Load Supply Current
Maximum Load Current,
V
OUT
= 3.3V
Switch Current Limit
Switch Current Limit
Maximum Load Current,
V
OUT
= 5V
No-Load Supply Current
T
A
= 25°C unless otherwise noted.
SWITCHING FREQUENCY (MHz)
0.20
EFFICIENCY (%)
POWER LOSS (W)
84
86
1.60
82
80
0.60 1.00
0.40
0.80 1.20
1.80
1.40 2.00
74
72
78
88
76
3.0
3.5
2.5
2.0
0.5
0
1.5
4.0
1.0
3980 G03
V
IN
= 12V
V
OUT
= 5V
I
OUT
= 2A
Typical perFormance characTerisTics
Efficiency, V
OUT
= 3.3V
Efficiency vs Switching Frequency
I
LOAD
(A)
0 0.5
EFFICIENCY (%)
1
2
3980 G01
1.5
V
IN
= 12V
V
IN
= 48V
f = 400kHz
D = DIODES, INC. SBR3U100LP
V
IN
= 24V
85
70
60
55
50
90
80
75
65