Datasheet

LT3475/LT3475-1
4
3475fb
Switch Current Limit
vs Duty Cycle
Switch Current Limit vs
Temperature
Oscillator Frequency
vs Temperature
Oscillator Frequency Foldback Oscillator Frequency vs R
T
Current Limit vs Output Voltage
TYPICAL PERFOR A CE CHARACTERISTICS
UW
LED Current vs V
ADJ
LED Current vs Temperature Switch On Voltage
V
ADJ
(V)
0
0
LED CURRENT (A)
0.25
0.50
0.75
1.00
1.25
1.50
0.25 0.5 0.75 1
3475 G01
1.25
T
A
= 25°C
TEMPERATURE (˚C)
–50
LED CURRENT (A)
0.8
1.0
1.2
25 75
3475 G02
0.6
0.4
–25 0
50 100 125
0.2
0
V
ADJ
= V
REF
• 7/30
V
ADJ
= V
REF
• 2/3
SWITCH CURRENT (A)
0
0
SWITCH ON VOLTAGE (mV)
100
200
300
400
0.5 1.0
1.5
2.0
3475 G03
500
600
T
A
= 25°C
DUTY CYCLE (%)
0
0
CURRENT LIMIT (A)
0.5
1.0
1.5
2.0
2.5
3.0
20 40 60 80
3475 G04
100
MINIMUM
TYPICAL
T
A
= 25°C
TEMPERATURE (°C)
–50
2.0
2.5
3.5
25 75
3475 G05
1.5
1.0
–25 0
50 100 125
0.5
0
3.0
CURRENT LIMIT (A)
V
OUT
(V)
0
0
CURRENT LIMIT (A)
0.5
1.0
1.5
2.0
0.5 2.5 3.0 3.52.01.0
1.5
4.0
3475 G06
2.5
3.0
T
A
= 25°C
TEMPERATURE (˚C)
–50
OSCILLATOR FREQUENCY (kHz)
600
650
700
25 75
3475 G07
550
500
–25 0
50 100 125
450
400
R
T
= 24.3kΩ
V
OUT
(V)
0
500
600
700
2.0
3475 G08
400
300
0.5 1.0 1.5 2.5
200
100
0
OSCILLATOR FREQUENCY (kHz)
T
A
= 25°C
R
T
= 24.3kΩ
R
T
(kΩ)
1
10
OSCILLATOR FREQUENCY (kHz)
1000
10 100
3475 G09
T
A
= 25°C