Board Design Signal Integrity

מק"ט: #7350 | משך קורס: 40 שעות אק'

“ALL EMI PROBLEMS BEGIN AND END IN THE PRINTED CIRCUIT BOARD (PCB)”
Printed circuit boards (PCBs), serve as the core, the nucleus, of any electronic system. They contain the processing circuits, the communication devices, the memory arrays and the input/output circuitry.
Contemporary components employ advanced technologies to achieve high speed propagation. In recent years, printed circuit boards have become increasingly complex. The use of high density VLSI (very large scale integrated circuits) on the one hand, combined with the increased processing speed and data rates, have led to the increased density of the circuits, requiring the placement of more components (and conductors) in much less “real estate” on the PCB.


New technology particularly entails the use of high speed digital circuits, responding to the need for increased processing rates of data.
The use of high speed-high edge rate digital circuits, acting like RF signals, along with the need for low power consumption, contributed to higher electromagnetic emissions from the circuits, on the one hand, and increased vulnerability of the circuits – on the other, leading to EMI PROBLEMS. A special problem also associated with the functional performance of high speed digital circuits themselves is that of “SIGNAL INTEGRITY”.


Most Hardware Engineers, however, have been seeking for 20 years old "rules of thumb".

  • Are the "rules of thumb" valid in your application?
  • Do you know on which assumptions are they based?
  • Do you know their origins?
  • Do you understand them?
  • Do they comply with your system requirements?
  •  

The proper design of printed circuit boards (PCBs) is a cost effective approach for the control of EMI in high speed circuits and is a necessity for ensuring the proper performance of the system.


The High Speed Board Design Course explores the High Speed Media and Technologies, based on scientific facts, design examples and case studies.
This course is essential for Hardware Design Engineers who seek to tell apart the superstitious beliefs from physical facts.

הקורס פעיל לקבוצות מטעם ארגונים בלבד, ניתן לשלוח פנייה רק אם מדובר בקבוצה
*שדות חובה
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מטרות

In just 5 days, the participant will acquire:

  • Fundamental scientific & technical knowledge of the problem and interference sources on printed circuit boards
  • Principles for the proper design considerations and know-how for the design of PCBs for EMC compliance
  • Know-how of a systematic approach for the proper design of printed circuit boards while implementing EMI control measures
  • Tools to cope with “daily” problems by choosing the most suitable solution

 

The participant will get acquainted with:

  • “Daily” problems & Solutions
  • Technical Definitions for terms related with high speed and ultra-high speed signal propagation

 

Ask questions to better understand the material!!!

Participants are also encouraged to bring forward actual design problems and questions they have encountered, which the instructor will attempt to assist in their solution.

תנאי קדם

  • Academic & Technical knowledge on the studied material
  • Guidelines and rules for hands on applications
  • Tools to cope with “daily” problems by choosing the most suitable solution

 

קהל יעד

  • Hardware Practical Engineers, Design Engineers, Team Leaders and Project Managers
  • Electrical, electronic and computer and process control engineers and technicians, who are involved in the design and development, qualification or engineering management of electronic and electrical equipment and in particular - in the design of high speed digital circuits.

The course is also intended to be useful for designers of printed circuit boards other than digital circuits (e.g., analog circuits and combined circuits)

נושאים

Introduction – Why Design for EMC and Signal Integrity?

  • What is EMC?
  • EMI, EMC…Definition of terms
  • Nature of an EMI problem
  • Why design for EMC on high speed digital printed circuit boards?
  • EMC vs Signal Integrity

 

Fundamental EMC Concepts

  • A primer of Maxwell's Equations
  • Spectral contents of signals
  • Parasitics and "real world" passive elements
  • Skin Effect, what causes it, skin depth and resistance
  • Current return paths, proximity effect
  • Common- and Differential mode currents
  • Electromagnetic emissions

 

Transmission Lines

  • What is Characteristic Impedance?
  • Basic Transmission Line Theory
  • Why use 50 impedance?
  • Termination Techniques

 

Signal Integrity

  • Introduction – What is Signal Integrity
  • Signal Integrity Noise Problems
  • Contemporary technologies & Signal Integrity Problems
  • What is High Speed?
  • Signal Integrity in the Design Flow
  • Signal Integrity Engineer in a Design Team

 

Noise Sources on Printed Circuit Boards

  • Noise in signal circuits
  • Noise in ground and power circuits
  • Crosstalk and coupling
  • Ground bounce (delta-I noise) on the circuit and its mitigation

 

Grounding and PCB Grounding design

  • The concept of “grounding” - what is “grounding”
  • Grounding topologies and “grounding tree” (including practical examples)
  • “Ground loops” and “opening” of Ground Loops
  • The design of the grounding system for EMC Control on PCBs

 

Power Integrity and Power Circuit Designs on PCBs

  • What is Power Integrity?
  • Coupling through power circuits
  • The necessity for decoupling
  • Review of capacitor types and their parameters
  • Decoupling capacitors & parasitic elements
  • Calculating the decoupling capacitor value
  • Decoupling & system bandwidth
  • PWR-GND inter-plane capacitance

 

DC/DC Power Supply Topologies

  • Introduction to switched and non-switched DC/DC topologies
  • Series regulators and LDOs
  • Basic switch mode regulators, buck and flyback
  • Power Supply Filtering, PI, T, L filters and ferrite beads

 

Reflections and Impedance Matching in Transmission Lines

  • PCB traces as transmission lines
  • Reflections on printed circuit board traces
  • Impedance control, impedance matching, trace termination and reflection reduction on PCBs
  • Trace routing
  • Transmission line configurations, propagation delay and characteristic impedance
  • Differential transmission line configurations
  • Vias, pads and straight right angle
  • Mirco-islands

 

Current Return Paths on PCBs

  • Current Density in the Return Path
  • Via "Picket Fence"
  • “Guard traces”, when and how, and trace separation rules
  • Return planes, GND, Vcc
  • Solid and gapped return planes, and bypassing
  • Vias, layer jumping and its effect on the return path

 

Crosstalk on PCBs

  • What is Crosstalk
  • Sources of crosstalk and its effect
  • Identifying the mutual coupling causes
  • Mutual Inductance and Capacitance
  • Common impedance coupling
  • Calculating the Crosstalk between signal traces
  • The crosstalk coefficient
  • Crosstalk in Differential Signals
  • Minimizing Crosstalk on PCBs

 

Step-by-Step PCB Design for EMC and Signal Integrity

  • Component placement topologies
  • Board stack up and layer allocation
  • Grounding and power topologies at the PCB
  • Layer allocation
  • Edge connectors
  • Edges of Planes
  • Routing of traces on the PCB
  • Vertical vs. Horizontal signal trace layout
  • Routing differential pairs

 

Clock Circuit Layout

  • Special problems associated with clock circuits
  • Clock circuit design and clock distribution
  • Spread-spectrum clock generators

 

Mixed Circuit Grounding – to Split or not to Split

  • Mixed analog-digital circuit design
  • Treatment of ADC and DAC –embedded circuits

 

PCB Design

  • Delay Lines and Matched Delays

 

Contemporary Ultra-High Speed Technologies

  • Uniqueness of Ultra-high-speed propagation
  • PCB Materials – The Signal Medium
  • Dielectric Constant – What is Permittivity
  • PCB Materials and Resistive/Dielectric Losses, Loss Tangent
  • Introduction to Ultra-High Speed Technologies
  • Differential digital busses, advantages and disadvantages
  • Technologies, LVDS, LVPECL, CML
  • DDR2 and DDR3 Technology

 

Edge Connectors

  • Why consider connectors?
  • Pin allocation in connectors
  • Ground and power return pins in connectors

 

A PCB Layout Checklist

  • The “Ten Commandments” in PCB Design

 

Summary and Wrap Up

  • Practical EMC Problems - discussion
  • Miscellaneous issues
תגיות