APW7061
Typical Characteristics (Cont.)
Reference Voltage vs. Junction Temperature
0.8
Reference Voltage (V)
0.798
0.796
0.794
0.792
0.79
-40
-20
0
20
40
60
80
100 120
Junction Temperature (°C)
Application Information
Component Selection Guidelines
Output Capacitor Selection
The s election of C
OU T
is determined by the required
effective series resist ance (ESR) and voltage rat ing
rat her t han t he ac tual c apacit anc e requirement .
Therefore select high performance low ESR capacitors
that are intended for switching regulator applications.
In some applications, multiple capacitors have to be
paralled to achieve the desired ESR value. If tantalum
capacitors are used, make sure they are surge tested
by the manufactures. If in doubt, consult the capacitors
manufac turer.
Input Capacitor Selection
The input capacitor is chos en based on the volt age
rat ing and the RMS c urrent rat ing. For reliable
operation, select the capacitor voltage rating to be at
C opyright
©
ANPEC Electronics C orp.
Rev. A.7 - Nov., 2005
10
least 1.3 times higher than the maximum input voltage.
The maximum RMS c urrent rating requirement is
approximately I
OUT
/2 , where I
OUT
is the load current.
During power up, the input capacitors have to handle
large amount of surge current. If tantalum capacitors
are us ed, make s ure they are surge t est ed by t he
manufact ures . If in doubt, c onsult t he c apac it ors
manufac turer.
For high frequency decoupling, a ceramic capacitor
between 0.1uF to 1uF can be connected between V
CC
and ground pin.
Inductor Selection
The inductanc e of the inductor is determined by the
output voltage requirement. The larger the inductance,
the lower the inductor’ current ripple. This will translate
s
www.anpec.com.tw
ANPEC [ ANPEC ELECTRONICS COROPRATION ]
