Diodes AL8808 - Manual (Page 8)

AL8808
Document number: DS35648 Rev. 2 - 2
8 of 20
www.diodes.com
January 2013
© Diodes Incorporated
NEW PROD
UC
T
AL8808
Typical Performance Characteristics
(1A LED Current) T
A
= +25°C unless otherwise stated.)
1 LED
2 LEDs
3 LEDs 4 LEDs 5 LEDs 7 LEDs
T = 25°C
L = 33µH
R
= 100m
A
SET
Ω
18 15 12 6 9 30 27 24 21
INPUT VOLTAGE (V)
Figure 26. LED Current Deviation vs. Input Voltage
5
4
3
2
-4
-5
0
DE
VI
A
TI
O
N
F
R
O
M
T
A
R
GE
T
C
U
R
R
EN
T (
%
)
1
-1
-2
-3
18 15 12 6 9 30 27 24 21
INPUT VOLTAGE (V)
Figure 27. Switching Frequency vs. Input Voltage
600
500
400
300
100
0
200
SW
IT
C
HIN
G
F
R
E
Q
UEN
C
Y
(k
H
z)
1 LED
2 LEDs 3 LEDs 4 LEDs 5 LEDs 7 LEDs
T = 25°C
L = 33µH
R
= 100m
A
SET
Ω
18 15 12 6 9 30 27 24 21
INPUT VOLTAGE (V)
Figure 28. LED Current Deviation vs. Input Voltage
1 LED
2 LEDs
3 LEDs
4 LEDs
5 LEDs
7 LEDs
T = 25°C
L = 68µH
R
= 100m
A
SET
Ω
5
4
3
2
-4
-5
0
D
EV
IA
T
IO
N
F
R
O
M
T
A
R
G
E
T
C
U
R
R
E
N
T
(
%
)
1
-1
-2
-3
18 15 12 6 9 30 27 24 21
INPUT VOLTAGE (V)
Figure 29. Switching Frequency vs. Input Voltage
300
250
200
150
50
0
100
SW
IT
C
H
IN
G
F
R
E
Q
U
E
N
C
Y
(k
H
z)
18 15 12 6 9 30 27 24 21
INPUT VOLTAGE (V)
Figure 30. LED Current Deviation vs. Input Voltage
1 LED
2 LEDs
3 LEDs
4 LEDs
5 LEDs 7 LEDs
T = 25°C
L = 100µH
R
= 100m
A
SET
Ω
5
4
3
2
-4
-5
0
D
EVI
A
T
IO
N
F
R
O
M
T
A
R
G
E
T
C
U
R
R
E
N
T
(%)
1
-1
-2
-3
18 15 12 6 9 30 27 24 21
INPUT VOLTAGE (V)
Figure 31. Switching Frequency vs. Input Voltage
200
180
160
80
20
0
60
SW
IT
C
H
IN
G
F
R
E
Q
U
EN
C
Y
(k
H
z)
140
100
120
40
1 LED