Discus Essential Principles of Signals on Interconnects 1. Why is it a good idea to not call the return path ground? 2. What is generated between the signal and return conductors at the beginning of a transmission line when a signal is launched? What will happen? 3. Is the signal the moving electrons in the conductor or the electric field in the dielectric? 4. What […]

Discus Categorizing Transmission Lines 1. What are the five families of transmission line types? 2. What is the difference between a uniform and nonuniform transmission line? 3. Why doesn’t a nonuniform transmission line have a characteristic impedance? 3.7 Review Questions 87 4. What is the difference between a single-ended transmission line and a differential pair transmission line? 5. What does the cross talk between two […]

Discus Five Impedances of a Transmission Line 1. What is the fundamental, basic definition of impedance? 2. What are the five different impedances that can be associated with a transmission line? 3. What is the instantaneous impedance of a transmission line? 4. The characteristic impedance of a uniform transmission line is 60 ohms. What is the initial input impedance a signal will see entering the […]

Discus The Reflection and Transmission Coefficient 1. What is the problem that results when the instantaneous impedance a signal sees changes? 2. What is the first goal in interconnect design to reduce reflection noise? What is the second goal? 3. What is the consequence if there were no reflections generated at an interference between two different characteristic impedance transmission lines? 4. What are the two […]

Discus Analyzing Reflections with the Bounce Diagram 1. What fundamentally causes ringing when viewing the output from a fast driver by a scope? 2. What does a bounce diagram describe? 6.7 Review Questions 155 3. What are two common features of a real transmission line system a bounce diagram does not do a good job of calculating? 4. If the source resistance is lower than […]

Discus Practical Applications of Transmission Line 1. What are the typical features of the signal on the compensation port of a scope? 2. Does the measured rise time of the signal into the scope increase with cable length? 3. If you want to efficiently fix a problem, what do you need to know about the problem? 4. If the root cause of the longer rise […]

Discus Electrical Models of Transmission Lines 1. What is the difference between the real world and the ideal world of electrical models? 2. What are the five ideal circuit element components found in all SPICE simulators? 3. What are three different measurement instruments that can measure properties of transmission lines? 4. What is special about the mathematical world? 5. What is special about the ideal […]

Order Principles of Operation Discussion 1. What does a TDR actually measure? 2. What feature of the interconnect corresponds to the time between the start of the signal coming out of the TDR and receiving the reflected signal back in the TDR? 3. What is the shape of the waveform coming out of the TDR and entering the interconnect? 4. If only one node inside […]

Order Practical TDR Measurements Assignment 1. What are the two most important measurements to take with a TDR before doing any other measurements? 2. Why is it important to always use a torque wrench? 3. What is the shape of the reflection from a connection that is not tight? 4. Why is the launch into a coax cable usually inductive? 5. What is the impedance […]

Discus Measure the Impedance or Dielectric Constant 1. What is the Dk of a dielectric a measure of? Practical Transmission Lines 314 2. What combination of materials contribute to the Dk of a laminate layer? 3. Why would the measured Dk of a stripline structure not be the Dk of each layer? 4. What are three ways of measuring the Dk of a transmission line? […]