Course #70
High-Speed PCB Design for EMC and Signal Integrity
October 15 - 19, 2012
. Dresden, Germany
We recommend you to submit your
preliminary or firm registration at least 4 weeks before course
start to ensure a seat on the course.
TECHNOLOGY FOCUS
All EMI problems begin and end on the Printed Circuit
Board. In recent years, PCBs have become increasingly complex. The
use of high density VLSI on the one hand, combined with the
increased processing speed and data rates on the other hand, have
led to the increased density of the circuits. The use of high
speed/high edge rate digital circuits, along with the need for low
power consumption, have contributed to higher electromagnetic
emissions from circuits, on the one hand, and increased sensitivity
of the circuits on the other, leading to Electromagnetic
Interference (EMI) problems.
A special problem is that of Signal Integrity (SI). For the
adequate control of EMI, strict international standards and
regulations have been developed worldwide. These standards require
the suppression of electromagnetic emissions from circuits and
systems, and their increased immunity to externally induced
interference. The proper design of PCBs is a cost effective
approach for the control of EMI in high-speed circuits.
COURSE CONTENT
This is an advanced design course, dealing with the
theory and design of PCBs for meeting EMC and SI objectives. The
course features understanding of the electromagnetic phenomena in
PCBs, and in particular in high-speed digital PCBs. The course
emphasizes practical applications, with mathematical derivations
kept to the minimum necessary. In addition, case studies and
practical "real life" examples will be provided.
Monday
Introduction - Why Design for EMC and
SI?
We will discuss the concepts of EMC and SI and describe
the similarities and differences between the two as they pertain to
circuit design and the primary parameters that govern interference
modes and system performance with respect to EMC and
SI.
Noise Sources on PCBs
The characteristics of noise sources on PCBs will be
discussed, with particular emphasis on noise in signal, power and
ground circuits. Coupling and interaction between circuits,
particularly crosstalk, will be discussed in detail.
Circuit Elements
Characteristics of real world circuit elements, with special
emphasis on parasitic inductance, capacitance and resistance will
be discussed.
Fundamentals of Grounding Design
The concept of grounding and basics of grounding system designs
will be presented. Design of the grounding tree and identification
and elimination of ground loops will be discussed in detail.
Application of the fundamental grounding theory to grounding on
PCBs will be presented.
Tuesday
Power Circuit Designs on PCBs
A discussion of the interaction via the power system on
the PCB will lead to the concept of decoupling, classical and
innovative decoupling strategies, filtering, and filter design for
EMI control. In particular, the generation of Parallel Plate
Waveguide Noise will be discussed.
Novel techniques for addressing "Ground Bounce" or delta-I Noise
and its mitigation such as Electromagnetic Band Gap (EBG) will also
be presented.
Reflections and Impedance Mismatch on High Speed Digital
PCBs
We now focus on the treatment of signal traces,
transmission lines, and the implication of the concept to PCB
design. Impedance mismatch, leading to reflections and noise are
discussed in detail, and design approaches, including impedance
matching, source and load termination topologies are
presented. The concept of "S-Parameters" for circuit analysis
will be presented.
Wednesday
Crosstalk on the PCB
The concept of crosstalk on PCB as a primary source of
EMI concerns and failures is discussed. Approaches for minimizing
crosstalk, with particular emphasis of routing guidelines, are
presented in detail.
PCB Design for EMC
Strategies for a systematic design approach of PCBs from
the standpoint of EMC and SI includes such design features as
layout, layer stacking, placement, power distribution and
grounding/reference systems.
Treatment of Mixed (Analog/Digital) Circuits
The problem of mixed analog/digital circuits is
presented. The discussion covers the problem of ADC and DAC
devices, and circuit design with one or multiple devices on one and
on multiple PCBs.
Thursday
Clock Circuits
The special problems associated with clock circuits and
clock signal distribution, including classical and novel approaches
for clock circuit design, are discussed.
Treatment of Special Signals in PCB Design
Some commonly used digital interfaces, such as LVDS circuit
design, are given particular attention.
Shielding on PCBs
Implementation of shielding as an EMI control measure,
particularly on PCBs, is discussed here.
Edge Connectors
Improper design of edge connectors may cause an otherwise good
design to fail both EMC and SI objectives. We will discuss the
proper design of edge connectors consistent with circuit design
with special emphasis on high-speed interfaces. Items covered
include pin allocation, layout of power, ground pins, and the
connector arrangement.
PCB Layout Guidelines
A verification checklist for PCB layout guidelines for
EMC and SI will be presented.
Friday
Measurement Fundamentals
EMC measurements, particularly the use of spectrum analysers and
oscilloscopes for observing system performance, will be
discussed.
Summary
Questions, examples presented by the participants, and practical
EMC and SI problems on PCBs will be treated in an interactive
manner.
Said about
the course from previous course participants:
"The course was relevant to all important aspects of PCB
design."
"I liked both the SI and EMI teaching as both are not always
covered in the same course."
" Right balance between theory and practical point of view."
"Practical and real examples."
"The enthusiasm of the teacher makes the subject easier to
learn."
"I like the concept of giving the basic understanding in the first
days and then putting it all together in the end."