Datasheet

LT3474/LT3474-1
4
3474fd
TYPICAL PERFORMANCE CHARACTERISTICS
Current Limit vs Duty Cycle
Switch Current Limit vs
Temperature
Current Limit vs Output Voltage
Oscillator Frequency vs
TemperatureOscillator Frequency vs R
T
Oscillator Frequency Foldback
LED Current vs V
ADJ
LED Current vs Temperature Switch Voltage Drop
V
ADJ
(V)
0
LED CURRENT (mA)
600
800
1000
1
3474 GO3
400
200
0
0.25
0.5
0.75
1.25
T
A
= 25°C
TEMPERATURE (°C)
–50
LED CURRENT (mA)
800
1000
1200
25 75
3474 G04
600
400
–25 0
50 100 125
200
0
V
ADJ
= V
REF
V
ADJ
= V
REF
/5
SWITCH CURRENT (mA)
0
700
600
500
400
300
200
100
0
3474 G05
500
1000 1500
SWITCH VOLTAGE DROP (mV)
T
A
= 25°C
DUTY CYCLE (%)
0
CURRENT LIMIT (A)
1.5
2
2.5
80
3474 G06
1
0.5
0
20
40
60
100
TYPICAL
MINIMUM (125°C)
MINIMUM (85°C)
TEMPERATURE (°C)
–50 –25
0
CURRENT LIMIT (A)
1
2.5
0
50
75
3474 G07
0.5
2
1.5
25
100
125
V
OUT
(V)
0
0
CURRENT LIMIT (A)
0.5
1
1.5
2
2.5
2
468
3474 G08
10 12
T
A
= 25°C
R
T
(kΩ)
10
100
OSCILLATOR FREQUENCY (kHz)
1000
100
3474 G09
T
A
= 25°C
TEMPERATURE (°C)
–50
400
OSCILLATOR FREQUENCY (kHz)
450
500
550
600
–25 0 25 50
3474 G10
75 100 125
R
T
= 80.6k
V
OUT
(V)
0
0
OSCILLATOR FREQUENCY (kHz)
100
200
300
400
500
600
0.5 1 1.5 2
3474 G11
2.5
T
A
= 25°C
R
T
= 80.6k