LT3508
TYPICAL PERFORMANCE CHARACTERISTICS
Efficiency, V
OUT
= 5V
95
90
EFFICIENCY (%)
85
80
75
70
65
V
IN
= 32V
90
T
A
= 25°C
f = 700kHz
V
IN
= 12V
V
IN
= 24V
EFFICIENCY (%)
80
75
70
65
60
0
0.5
1
LOAD CURRENT (A)
1.5
3508 G01
Efficiency, V
OUT
= 3.3V
T
A
= 25°C
f = 700kHz
85
85
V
IN
= 12V
V
IN
= 24V
80
EFFICIENCY (%)
75
70
65
60
55
Efficiency, V
OUT
= 1.8V
T
A
= 25°C
f = 1MHz
V
IN
= 3.3V
V
IN
= 5V
V
IN
= 12V
V
IN
= 32V
0
0.5
1
LOAD CURRENT (A)
1.5
3508 G02
0
0.5
1
LOAD CURRENT (A)
1.5
3508 G03
Feedback Voltage
0.810
3.0
2.5
FEEDBACK VOLTAGE (V)
0.805
CURRENT LIMIT (A)
2.0
1.5
1.0
0.5
0.790
–50 –25
Switch Current Limit
vs Temperature
3.0
2.5
CURRENT LIMIT (A)
2.0
1.5
1.0
0.5
0
0
25 50 75 100 125 150
TEMPERATURE (°C)
3508 G05
Switch Current Limit
vs Duty Cycle
T
A
= 25°C
TYPICAL
MINIMUM
0.800
0.795
0
25 50 75 100 125 150
TEMPERATURE (°C)
3508 G04
0
–50 –25
0
20
40
60
DUTY CYCLE (%)
80
100
3508 G06
Switching Frequency vs R
T
1000
T
A
= 25°C
SWITCHING FREQUENCY (MHz)
1.2
1.0
0.8
0.6
0.4
0.2
Switching Frequency
vs Temperature
R
T
= 33.2k
SWITCHING FREQUENCY (MHz)
3.0
2.5
Switching Frequency Foldback
T
A
= 25°C
R
T
= 7.50k
2.0
1.5
1.0
0.5
0
0
100 200 300 400 500 600 700 800
FEEDBACK VOLTAGE (mV)
3508 G09
100
R
T
(kΩ)
10
R
T
= 33.2k
R
T
= 169k
1
0.1
1
FREQUENCY (MHz)
10
3508 G07
0
–50 –25
0
25 50 75 100 125 150
TEMPERATURE (°C)
3508 G08
3508fb
4
LINER [ LINEAR TECHNOLOGY ]
