After establishing what a PCB transmission line is and talking about signal speed and propagation delay, and the critical length, the controlled impedance, and the rise/fall time of a PCB transmission line, we discussed impedance discontinuity and signal reflection. Today, we are going to explain how to analyze a PCB transmission line using quantities, such as voltages and currents, and line parameters, such as resistance, inductance, capacitance, and conductance.
After explaining the importance of the signal speed and propagation delay in a PCB transmission line, we are now going to talk about the transmission line effects, the critical length, the rise/fall time and when the length of an interconnection is to be considered as a controlled impedance transmission line.
During DesignCon 2018, we interviewed many PCB experts. Antonio Ciccomancini Scogna is one of them. He works as a Principal Engineer at Samsung, and part of his mission is to solve signal integrity issues that can appear when designing printed circuit boards for powerful smartphones.
Last week, we talked about what a PCB transmission line is. We are now going to focus on the technical side and discuss signal speed and propagation delay, two factors that have a great impact on a transmission line.
A PCB transmission line is a type of interconnection used for moving signals from their transmitters to their receivers on a printed circuit board. A PCB transmission line is composed of two conductors: a signal trace and a return path which is usually a ground plane. The volume between the two conductors is made up of the PCB dielectric material.
- Electromagnetic interference, or EMI as it is commonly known, is a major cause of signal integrity problems for PCBs. All electronic circuits generate EMI and all are affected by it.