AN-6094
© 2012 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.0 • 9/27/12
19
7. Test Results of Design Example
To show the validity of the design procedure presented in
this application note, the converter of the design example
was built and tested. All the circuit components are used
as designed in the design example.
Figure 29 shows the measured efficiency for different
load conditions. The average efficiencies at 115 V
AC
and
230 V
AC
condition are 74.96% and 72.05%, respectively.
Figure 30 shows the measured no-load power
consumption at different line voltages. Even in the
264 V
AC
AC line, the no-load standby power consumption
is less than 10 mW, meeting the five-star level of new
power consumption regulation for charger. Table 2 shows
the loss breakdown for the standby power consumption
for 90 V
AC
and 264 V
AC
.
Figure 31 shows the measured output voltage and output
current curve. The output current is regulated between 1 A
and 1.2 A for output voltage from 5 V down to 1 V.
Figure 29. Measured Efficiency
Figure 30. Standby Power Consumption
Table 2. Loss Breakdown for Standby Power
Consumption
90V
AC
264V
AC
RCD Clamping Circuit
2.19
mW 1.19
mW
MOSFET Loss
0.52
mW 1.61
mW
Output Voltage Divider Resistor
(R
VS1
and R
VS2
)
0.26
mW 0.26
mW
IC Consumption
1.52
mW 1.56
mW
Secondary-Side Feedback Circuit
3.61
mW 3.61
mW
Output Diode
1.8
mW 1.8
mW
Total (Estimated)
9.9
mW 10.3
mW
Total (Measured)
8.1
mW 9
mW
0.2
Io (A)
0.3
0.4
0.5
0.1
0.7
0.8
0.9
1.0
0.6
1.1
1.2
1.3
Vo (V)
1
2
3
4
5
6
Figure 31. Output Voltage and Current Regulation
74.37
75.58
75.54
74.33
69.07
71.39
73.33
74.38
66.0
68.0
70.0
72.0
74.0
76.0
78.0
0
20
40
60
80
100
E
ff
ic
ie
n
cy (
%
)
% Load
115Vac: Avg=74.96%
230Vac: Avg=72.05%
