| |
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| Input data |
Nm= |
0.084 |
|
Minimum Secondary to Primary Turn Ratio |
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|
| |
Vbn= |
407 |
Vdc |
Nominal Average DC Boost Voltage |
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| |
Vbx= |
450 |
Vdc |
Maximum Boost Voltage |
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Vt= |
2.84 |
V |
Max voltage drop, Bridge Switches |
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| |
fdc= |
180 |
kHz |
Switching Frequency, DC/DC Converter |
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tdc= |
5.56 |
us |
Switching Period, DC/DC Converter |
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Impk= |
2.1 |
A |
Peak magnetizing current |
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Ddcn= |
86.8 |
% |
Nominal DC/DC Stage Duty Cycle |
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Iprrms= |
7.6 |
Arms |
RMS Current, Transformer Primary |
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Iscrms= |
45.1 |
Arms |
RMS Current, Transformer Secondary |
Eq.
end to end - Idc |
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| |
Ioutn= |
90.00 |
Adc |
Nominal Output Current |
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| |
ks= |
1 |
|
1 for Center Tap, 2 for Current
Doubler |
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| |
Icd= |
6.0 |
A/mm2 |
Current density |
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| |
Smp= |
3.7 |
mm |
Safety margin, Pri/HF winding, mm |
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| |
Sms= |
3.1 |
mm |
Safety margin, Sec/LF winding, mm |
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| |
Whm= |
8.5 |
mm |
Min winding height, mm |
E55/28/21 |
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| |
Wwm= |
33.5 |
mm |
Min winding width, mm |
E55/28/21 |
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| |
Ht= |
21.0 |
mm |
Core height or "C"
dimension |
E55/28/21 |
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| |
Ltm= |
88.5 |
mm |
Min turn length |
E55/28/21 |
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| |
le= |
124.0 |
mm |
Magnetic path length |
E55/28/21 |
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Ae= |
353 |
mm2 |
Magnetic core area, effective |
E55/28/21 |
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Am= |
345 |
mm2 |
Magnetic core area, minimum |
E55/28/21 |
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Vm= |
44,000 |
mm3 |
Magnetic volume |
E55/28/21 |
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| |
ur= |
1,800 |
|
u, ungapped core, no DC bias |
3F3 |
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| |
Bmax= |
0.30 |
T |
Maximum flux density @130°C |
3F3 |
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| |
uh= |
99.5 |
% |
Permeability @ Hpk |
3F3 |
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nctr= |
1 |
|
Number of core sets |
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| Intermediate |
Ltm= |
88.5 |
mm |
Min turn length, nctr sets |
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| data |
Ltn= |
106.8 |
mm |
Average turn length, nctr sets |
E55/28/21 |
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Aet= |
353 |
mm2 |
Magnetic core area, effective, nctr
sets |
E55/28/21 |
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Amt= |
345 |
mm2 |
Magnetic core area, minimum, nctr
sets |
E55/28/21 |
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Vmt= |
44,000 |
mm3 |
Magnetic volume, nctr sets |
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Vc= |
31,214 |
mm3 |
Copper volume |
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Vt= |
75,214 |
mm3 |
Total transformer volume |
E55/28/21 |
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ALc= |
10.0 |
nH/T2 |
AL, primary coil only |
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ALo= |
6,439 |
nH/T2 |
AL, ungapped core, no DC bias |
E55/28/21-3F3 |
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ALot= |
6,439 |
nH/T2 |
AL, ungapped core, no DC bias, nctr
sets |
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| |
Llk= |
|
uH |
Primary leakage inductance |
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Cpri= |
230 |
pF |
Primary capacitance |
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| Output data |
Npmin= |
6.0 |
|
Minimum Number of turns, Primary |
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Np= |
12.0 |
|
Primary Number of turns, chosen |
> 2 x Npmin |
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Nsc= |
1.0 |
|
Secondary Number of turns, calculated |
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Ns= |
1.0 |
|
Secondary Number of turns, chosen |
2 x
Ns end to end |
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Bpk= |
0.12 |
T |
Actual peak flux density, steady
state |
OK |
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kw= |
1 |
|
1 for 4 portions, 2 for 8 portions |
4
winding portions |
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N= |
0.0833 |
|
Actual Secondary to Primary Turn
Ratio |
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Lm= |
461 |
uH |
Magnetizing inductance |
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Idcpk= |
1.6 |
A |
Maximum DC current |
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AL= |
3,202 |
nH/T2 |
Core Al, ungapped, bias @ Hpk |
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Gap0= |
0.04 |
mm |
Core gap, no fringe effect |
x 2 |
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Gap= |
0.04 |
mm |
Core gap, closer to real |
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dB= |
116 |
mT |
Half of B peak to peak variation |
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Power Transformer Loss |
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| Intermediate |
Pcld= |
251 |
mW/cm3 |
Philips Ferrite 3F3 material |
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|
| data |
Dpenm= |
0.188 |
mm |
Penetration depth, mm |
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Dpen= |
7.4 |
mil |
Penetration depth, mil |
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Smp= |
147 |
mil |
Safety margin primary, mil |
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Sms= |
122 |
mil |
Safety margin secondary, mil |
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Ww= |
1.319 |
inch |
Winding width, available |
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Ltn= |
4.204 |
inch |
Average turn length |
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Wp= |
1.025 |
inch |
Primary winding width |
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kfr= |
1 |
|
1 for copper foil, 2 for round wire |
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Cs= |
4.0 |
mil |
Copper
foil thickness |
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Dp= |
1.9 |
mil |
Thickness, primary (required by
current density) |
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|
5.0 |
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Dpc= |
4.0 |
mil |
Copper
thickness |
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Qp= |
0.54 |
|
Layer thickness/depth penetration,
primary |
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Pp= |
6.0 |
|
Number of layers per winding portion,
primary |
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Frp= |
1.34 |
|
Rac/Rdc ratio, primary |
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Ap= |
2.65 |
mm2 |
Cross section area, primary |
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Ws= |
1.075 |
inch |
Secondary winding width |
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| |
Ds= |
10.8 |
mil |
Thickness secondary required by
current density |
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Dsc= |
20.0 |
mil |
Thickness, secondary, chosen |
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Qs= |
2.71 |
|
Layer thickness/depth penetration,
secondary |
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Pbs= |
1.0 |
|
Number of layers per winding portion,
secondary |
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Frs= |
2.71 |
|
Rac/Rdc ratio, secondary |
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| |
As= |
13.9 |
mm2 |
Cross section area, secondary |
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| |
Wff= |
53.8 |
% |
Winding height, fill factor |
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Tc= |
125.0 |
°C |
Actual copper temperature |
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| Output data |
Ptcrl= |
11.0 |
W |
Core Power Loss, 3F3 |
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| |
Pgap= |
0.0 |
W |
Gap related loss |
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Rdcp= |
12.1 |
mOhm |
DC Primary resistance |
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Racp= |
16.2 |
mOhm |
AC Primary resistance |
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Rdcs= |
0.4 |
mOhm |
DC Secondary resistance |
end to end |
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Racs= |
1.0 |
mOhm |
AC Secondary resistance |
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Ptpl= |
0.9 |
W |
Primary copper loss |
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Ptsl= |
2.9 |
W |
Secondary copper loss |
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Ttcu= |
3.8 |
W |
Total Copper loss |
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Pttl= |
14.9 |
W |
Power Transformer total loss |
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| |
Rth= |
4.1 |
°C/W |
Rth, toroid, open wound, natural
convection |
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dT3= |
61 |
°C |
Core Temperature Rise, 3F3 |
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| The coupling coefficient between primary and secondary is
assumed to be 1. |
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| We suggest using class H(180°C) for Power Magnetics (Boost
Inductor, Power Transformer and Output Inductor). |
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| For ferrites cores (Philips 3F3, Magnetics R, Siemens N87): |
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| Guaranteed Curie temperature: 200°C. |
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| Saturation flux density: 0.33@100°C, 0.30@130°C, 0.27@160°C. |
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| The operating core temperature is assumed to be 100°C for
core loss calculation. |
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| Minimum loss would be at 80-90°C. |
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| Maximum core operating temperature should be <160°C
(Tc=200°C-40°C margin). |
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| The accuracy of the formulas for core loss is expected to be
±10%. |
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| The accuracy of the formulas for temperature rise is expected
to be ±30%. |
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| Temperature rise is for natural convection cooling. |
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| For forced (fan) cooling the temperature rise could be 1/2 to
1/3, depending on airflow. |
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| SMPS Power Supplies, Inc. |
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| Doing The Right Thing Is The Right Thing To Doä |
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| www.PowerSupplies.net |
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| www.GoToPower.net |
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| Copyright © 1998-2005 SMPS Power Supplies,
Inc. All rights reserved. |
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| Copyright © 1990-1997 LCD Consulting |
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| Copyright © 1979-1989 Constantin Darius Livescu |
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