User guide

AL8807Q
Document number: DS36904 Rev. 1 - 2
8 of 16
www.diodes.com
March 2014
© Diodes Incorporated
A
L8807Q
Typical Performance Characteristics 1.3A LED Current (cont.) (@T
A
= +25°C, unless otherwise specified.)
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 25. LED Current Deviation vs. Input Voltage
10
8
2
0
-8
-10
LED
C
U
R
R
EN
T
E
R
R
O
R
(%)
4
-4
-6
-2
6
5 LEDs
6 LEDs
7 LEDs
8 LEDs
L = 100µH
R = 77m
T = 25°C
V = Open
S
A
CTRL

2 LEDs
3 LEDs
4 LEDs
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 26. Switching Frequency vs. Input Voltage
250
200
100
0
SWI
T
C
H
IN
G
F
R
E
Q
U
EN
C
Y
(k
H
z)
150
1 LED
50
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 27. LED Current Deviation vs. Input Voltage
10
8
2
0
-8
-10
LED
C
U
R
R
EN
T
E
R
R
O
R
(%)
4
-4
-6
-2
6
5 LEDs
6 LEDs
7 LEDs
8 LEDs
L = 68µH
R = 77m
T = 25°C
V = Open
S
A
CTRL

2 LEDs
3 LEDs
4 LEDs
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 28. Switching Frequency vs. Input Voltage
300
250
150
0
SWI
T
C
H
IN
G
F
R
E
Q
U
EN
C
Y
(k
H
z)
200
100
1 LED
50
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 29. LED Current Deviation vs. Input Voltage
10
8
2
0
-8
-10
LED
C
U
R
R
EN
T
E
R
R
O
R
(%)
4
-4
-6
-2
6
5 LEDs
6 LEDs
7 LEDs
8 LEDs
L = 33µH
R = 77m
T = 25°C
V = Open
S
A
CTRL

2 LEDs3 LEDs
4 LEDs
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 30. Switching Frequency vs. Input Voltage
600
500
300
0
SWI
T
C
H
I
N
G
F
R
E
Q
U
E
N
C
Y
(k
H
z)
400
200
1 LED
100