Ap8802, 1a led step-down converter, Application information – Diodes AP8802 User Manual
Page 9
AP8802
1A LED STEP-DOWN CONVERTER
AP8802
Document number: DS31766 Rev. 9 - 2
9 of 19
www.diodes.com
May 2012
© Diodes Incorporated
Application Information
(cont.)
AP8802 SO-8 Minimum Recommended Inductor
8% Accuracy, <70°C Case Temperature
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
1
2
3
4
5
6
7
8
9
10
11
12
Supply Voltage (V)
Figure. 18 SO-8 Recommended Inductor with 700mA LED Current
NUM
BE
R o
f L
E
Ds
Capacitor Selection
The small size of ceramic capacitors makes them ideal for AP8802 applications. X5R and X7R types are recommended because they retain
their capacitance over wider voltage and temperature ranges than other types such as Z5U. A 2.2
μF input capacitor is sufficient for most
intended applications of AP8802.
A 4.7
μF input capacitor is suggested for application with an input voltage equal or higher than 40V.
Diode Selection
Schottky diodes, e.g. B2100 or B1100, with their low forward voltage drop and fast reverse recovery, are the ideal choice for AP8802
applications.