al8805 Diodes, Inc., al8805 Datasheet - Page 5

• Manufacturer Part Number: al8805
• Description: High Efficiency 30v 1a Buck Led Driver
• Manufacturer: Diodes, Inc.

Typical Performance Characteristics Continued
AL8805
Document number: DS35030 Rev. 1 - 2
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
400
350
300
250
200
150
100
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0%
1
0
-40
LED Current Error
0
R
SET
Duty Cycle = 5%
= 150mΩ, L = 68µH, V
igure 9. SW R
20%
Figure 7. I
-15
Figure 11. PWM dimming
50
Ambient Temperature (°C)
10
40%
LED
PWM Duty Cycle
Time (µs)
DS(ON)
vs PWM duty cycle
100
35
IN
vs temperature
= 12V, 1 LED Load, T
60%
I
LED
150
60
V
V
R
CTRL
SET
SET
V
L = 68µH
80%
IN
= V
1LED
= Open
I
= 150mΩ
LED
V
= 12V
CTRL
IN
85
V
SW
= 12V
200
A
= 25°C
20
18
16
14
12
10
8
6
4
2
0
100%
www.diodes.com
110
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
5 of 16
HIGH EFFICIENCY 30V 1A BUCK LED DRIVER
F
130
125
120
115
110
105
100
300
250
200
150
100
(T
95
90
85
80
100%
50
90%
80%
70%
60%
50%
40%
30%
20%
10%
0
A
0%
0
= 25°C unless otherwise stated)
0
Figure 10. SW Output switching characteristics
6
Figure 12. Duty cycle vs Input voltage
Figure 8. SW R
9
5
2
12
10
V
SENSE
R
L = 68µH
V
1LED Load
Input voltage (V)
15
Time (µs)
DS(ON)
IN
SET
= 12V
4
= 150mΩ
V
IN
15
18
vs input voltage
(V)
21
20
L = 33µH
R
T
2 LED
AL8805
6
A
© Diodes Incorporated
S
September 2010
V
V
T
= 25°C
24
= 150mΩ
A
CTRL
SET
= 25°C
V
= V
= Open
SW
25
27
IN
8
30
18
16
14
12
10
8
6
4
2
0
-2
30