DC-DC converter design
AN4070
14/53
Doc ID 022934 Rev 1
HF transformer design
The design is based on the specifications reported in
Table 5
and has been used to provide
the main parameters required by HF transformer manufacturers for the realization of the
prototypes.
The design procedure and equations are shown in the section below.
1.
Calculation of total transformer power:
Equation 20
Table 5.
HF transformer specifications
Specification Value
Turns ratio
2.6
RMS input current
4.7 A
Nominal output voltage
380 V
Minimum output voltage
370 V
Output current
1.77 A
Switching frequency
35 kHz
Efficiency 98%
Max. operating flux density
0.05T
Window utilization
0.3
Duty cycle
0.45
Temperature rise
30 °C
W
P
P
T
outT
T
app
1
.
255
98
.
0
250
_
=
=
=
η
