Do Differential Pairs Need Ground? Explained by Eric Bogatin

Explore the importance of ground in differential pair signals for PCB layout and board design in this comprehensive 42-minute video featuring expert insights from Eric Bogatin. Delve into topics such as real differential pairs versus single-ended lines, transformer-coupled pairs, cable versus PCB routing, common mode versus differential mode, and the impact of return planes. Learn through simulations and examples comparing single-ended and differential signals in various scenarios, including cables and PCBs without ground planes. Gain valuable knowledge on tightly versus loosely coupled differential pairs, impedance considerations, and practical applications to enhance your high-speed digital design skills.

What is this video about
P & N
Real differential pair vs. two single ended lines
Differential pair going through a transformer vs. ground
Are diff pairs routed on board different from diff pairs in cables?
Differential vs. common
What if a differential pair doesn't have any return plane - examples explained
Simulation of a single ended signal vs. return current path
Simulation differential pair signals vs. return current path
Tightly vs. loosely coupled differential pairs
Differential pairs vs. return plane far away
Example 1: Single ended signal in cable
Example 2: Single ended vs. differential signal in cable
Results: Impedance graphs
Example 3: Single ended vs. differential signal in PCB without GND plane