To reduce interference and improve signal integrity

Presented by Dr. Tom Van Doren

Course Content and Schedule

8:00 am Check-in and Refreshments
8:30 am to 5:00 pm

1. Introduction

• Circuit board EMC problem areas
• EMC design guidelines
• References
• A circuit board in a plastic case
• An example of radiated emissions

2. Signal Routing, Field Containment, and Resonance

• Controlling the current path
• Concept of least impedance
• Routing to contain electric and magnetic fields
• Understanding the effects of resonance on signal integrity and emissions
• Identifying the radiation source on a dual processor circuit board
• Reducing emissions from a laptop computer

3. Transmission Line Effects

• When is a line electrically long?
• Source versus load matching
• Selecting the optimum Zο value
• Demonstration of impedance mismatch

4. Noise Coupling Mechanisms, Unintended Antennas, and Diagnostic Techniques

• Review of energy coupling mechanisms
• Identifying unintended antennas
• Example boards with unintended antennas
• Using current and field probes to diagnose EMI problems
• Controlling the path of large amplitude, low frequency currents

5. Filtering Conducted Noise

• Series and shunt filter strategies
• Effect of source and load impedances on selecting the correct strategy
• Reducing the mutual inductance of shunt mounted capacitors
• Examples of filtering at board connectors
• Characteristics of ferrite beads

6. Circuit Board Grounding Issues

• Reasons for grounding
• Understanding the differences between grounding and routing
• Grounding an A/D converter
• How to ground a circuit board to an external metal chassis
• Examples of board to chassis grounding connections

7. DC Power Distribution and Decoupling

• Power current paths for single-ended and differential signaling
• Maximizing power bus interplane capacitance
• Minimizing decoupling capacitor connection inductance
• Using stripline power routing to contain field

8. Component Placement and Layer Stackup

• Connector locations and pin assignments
• Stackup options for 4, 6, and 8 layer boards