User guide

AL8807Q
Document number: DS36904 Rev. 1 - 2
5 of 16
www.diodes.com
March 2014
© Diodes Incorporated
A
L8807Q
Typical Performance Characteristics (cont.) (@T
A
= +25°C, unless otherwise specified.)
Figure 11 SW Output Rise Time Figure 12 SW Output Fall Time
LED Current
LED Current
Error
L = 68H, R = 150m
T = 25C, V = 12V
CTRL = PWM, f = 500Hz
1 LED
S
AIN
PWM
020406080100
PWM DUTY CYCLE
Figure 7. I vs. PWM Duty Cycle
LED
9
8
7
6
4
3
2
0
LED CURRENT ERROR (%)
5
1
0.8
LED CURRENT (A)
0.7
0.6
0.5
0
0.4
0.3
0.2
0.1
0
20
40
60
80
100
120
140
160
180
200
0 5 10 15
20 25 30
R (m)
DS(ON)

V (V)
R vs. Input Voltage
IN
DS(ON)
V = Open
V = V 12V
T = 25C
CTRL
SET IN
A

-40 -15 35 60 11010 85
Ambient Temperature ( C)
Figure 9. SW R vs. Temperature

DS(ON)
V = Open
V = V= 12V
CTRL
SET IN
400
250
150
100
R
(m )
DS(ON)

350
300
200
6 9 12 15 18 21 24 27 30 33 36
INPUT VOLTAGE (V)
Figure 10. Duty Cycle vs. Input Voltage
100
90
80
70
60
40
30
20
10
0
50
D
U
T
Y
C
Y
C
LE (%)
2 LEDS
3 LEDS
L = 68µH
R = 100m
T = 25°C
V = Open
S
A
CTRL
