"Controlling Conducted & Radiated Emissions by   Design"  has gone  through  significant  revisions.

New  document  is called "  Controlling  complex Conducted  and  Radiated  Emissions and  Cross Talk  issues  with  Innovative  and  Practical  approaches"

-The  shorter  time-to-market  cycles  have  lead  to  the  development  of  this  document which ensures system  level electrical  functionality  and  electromagnetic  compatibility  at first (in most cases) / second  prototype  stages only  of  a  product,  rather  than expensive several  revisions.

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This document is a  most comprehensive document you will  ever find out there in the  EMI/EMC area of  specialization. It is full of experimental results gathered over several years in the PC, telecommunication, networking and electrical industries. This document also  provides references to more than  12  books for  further study of  materials discussed in this document, one of which also describes about filter softwares available on the market.

"Another term I introduced was, an embedded capacitance.  There is PCB space available on all layers under  cable header on the PCB at I/O connection.  This capacitor is intended for common mode noise signals filtering at I/O, it may also  provide protection against ESD (electrostatic discharge). The embedded capacitor will have one plate common to CGND and other individual plates connect to each trace as shown below in  fig. 4a. This arrangement can  save  you many discrete capacitors!"

" The Trace Inductance and  Via models:
 Reference book #10 has  covered  this  topic  in  much  more  details. I shall present  this topic with  few  examples, which  has  proven the necessity of  understanding  these issues at  early on  stages of  a  product, such  as first prototype. There  are  several scenarios one must take  into  account when designing very high frequency circuits. By high  frequency I mean fundamental clock frequency (>1MHz), or rise or  fall times of  the  order of  few nano seconds or less. However, it is  also possible clock  signals with clock  frequencies much  less than 1 MHz, and  rise and fall times in the nano seconds range could  have Fourier spectrum extending all the way in  the hundreds of  Megahertz range.

(a) Depending  upon frequency or rise/fall times or  in other  words the desired Band width for the signal to  be  transmitted from source to receiver, designer has  to use micro-strip transmission lines or  strip-line transmission lines. Strip lines are  useful  for  relatively  low frequency design as  compared to microstrip transmission lines. However, one great advantage of  using strip line technique, provides shielding from one layer to the other as well.

 Examples:
            In  case of  a  50 ohm micro-strip transmission line, a  capacitance of 5pf/inch, the  value of  inductance

 will be  Z=    (L/C)

 12.5nH/inch.

(b) Trace without an image  plane or  image plane is at  an infinite distance (usually enclosure for common mode noise signal) from it.
 Inductance of a Wire:

 L=5.08 *Len*[ln(4*Len/d)-0.75]
Where, L= inductance in nH, Len= length in inches ....."

And much more..............., you will be glad to have  this document!

Thank you.

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