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 resource from EMC Standards EMC design of Switching Power Converters Part 4 - Design techniques for HF isolating transformers
Transcript of Another EMC resource from EMC Standards...EMC design of Switching Power Converters Part 4 - Design...
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
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
Contents
all
all three plus
4.1 Introduction to the example
something
herethere
from the start of the project
when if
4.2 How the interwinding capacitance causes emissions
allalways always
cannot
But it is not what actually happens!
antiphase
outout
much lower
mightcannot
dV/dt
dV/dt dI/dt
4.3 Reducing emissions with an interwinding shield (or two, or more)
dV/dt
4.4 Reducing emissions with primary-secondary capacitors
Important Safety Note:
some
some
dV/dt
4.5 Using “buried” PCB capacitance for frequencies above 100MHz
”
4.6 Safety issues for capacitors that cross galvanic isolation barriers
neverapproved
inside
surfaces
internal
4.7 Connecting to interwinding shields, cores, and primary-secondary capacitors
4.8 Everything resonates
4.9 Connecting interwinding shields, cores, and primary-secondary capacitors to earth/ground/chassis/frame/etc.
However
in itself
4.10 Construction of the isolating transformer
dI/dt
dV/dtdV/dt
outside
