Another EMC resource from EMC Standards...EMC design of Switching Power Converters Part 4 - Design...
Transcript of Another EMC resource from EMC Standards...EMC design of Switching Power Converters Part 4 - Design...
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Helping you solve your EMC problems
1 Brassey Road, Old Potts Way, Shrewsbury, SY3 7FA T:+44 (0) 1785 660 247 E:[email protected]
Another EMC resourcefrom EMC Standards
EMC design of Switching Power Converters Part 4 -Design techniques for HF isolating transformers
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Helping you solve your EMC problems
9 Bracken View, Brocton, Stafford ST17 0TF T:+44 (0) 1785 660247 E:[email protected]
Another EMC resourcefrom EMC Standards
EMC design of Switching Power Converters Part 4 -Design techniques for HF isolating transformers
![Page 3: Another EMC resource from EMC Standards...EMC design of Switching Power Converters Part 4 - Design techniques for HF isolating transformers. Helping you solve your EMC problems. 9](https://reader035.fdocuments.us/reader035/viewer/2022062611/6128108d602a381eee39362c/html5/thumbnails/3.jpg)
Contents
all
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all three plus
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4.1 Introduction to the example
something
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herethere
from the start of the project
when if
4.2 How the interwinding capacitance causes emissions
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allalways always
cannot
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But it is not what actually happens!
antiphase
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outout
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much lower
mightcannot
dV/dt
dV/dt dI/dt
4.3 Reducing emissions with an interwinding shield (or two, or more)
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dV/dt
4.4 Reducing emissions with primary-secondary capacitors
Important Safety Note:
some
some
dV/dt
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4.5 Using “buried” PCB capacitance for frequencies above 100MHz
”
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4.6 Safety issues for capacitors that cross galvanic isolation barriers
neverapproved
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inside
surfaces
internal
4.7 Connecting to interwinding shields, cores, and primary-secondary capacitors
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4.8 Everything resonates
4.9 Connecting interwinding shields, cores, and primary-secondary capacitors to earth/ground/chassis/frame/etc.
However
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in itself
4.10 Construction of the isolating transformer
dI/dt
dV/dtdV/dt
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outside