Diodes AP8802H - Manual (Page 5)

AP8802H
60V 1A LED STEP-DOWN CONVERTER
AP8802H
Document number: DS32227 Rev. 6 - 2
5 of 14
www.diodes.com
May 2012
© Diodes Incorporated
PRELIMINARY
NEW PROD
UC
T
Typical Characteristics (T
A
= +25°C, V
IN
= 60V, L = 68µH; unless otherwise stated.)
OUT
P
UT
CU
RRE
NT
DEVIA
T
ION (
%
)
INPUT VOLTAGE (V)
Figure. 8 LED Current vs. Input Voltage
6 12 18 48 54 60 24 30 36 42
10
-10
8
-8
-6
-4
0
2
4
6
-2
INPUT VOLTAGE (V)
Figure. 9 Efficiency vs. Input Voltage
6 12 18 48 54 60 24 30 36 42
E
F
F
IC
IE
N
C
Y
(%
)
100
95
65
75
80
85
90
70
INPUT VOLTAGE (V)
Figure. 10 Switching Frequency vs. Input Voltage
6 12 18 48 54 60 24 30 36 42
SW
IT
C
H
IN
G
F
R
E
Q
U
E
N
C
Y
(k
H
z)
500
0
450
50
100
150
250
300
350
400
200
SUPPLY VOLTAGE (V)
Figure. 11 Duty Cycle vs. Input Voltage
6 12 18 48 54 60 24 30 36 42
D
U
T
Y
C
Y
C
LE
(
%
)
100
0
90
10
20
30
50
60
70
80
40
Figure. 12 Steady State Waveforms
Figure. 13 Start-Up Showing LED Current Soft Start