差分信号知识讲座(ppt 69页)

Differential Signaling Definition
Voltage Parameters
Common mode parameters
Differential mode parameters
Current mode logic (CML) buffer
Relate to parameters
Modeling & simulation
Timing parameters
Clock recovery
Embedded clock
AC coupling
Common mode response
Issues with simulation
8B10B encoding
DC balanced codes
Duty Cycle distortion
Cycle
All electrical signal circuits require a loop or return path.
Single ended signal subject several means of distortions and noise.
Ground or reference may move due to switching currents (SSO noise). We touched on this in the ground conundrum class.
A single ended receiver only cares about a voltage that is referenced to its own ground.
Electromagnetic interference can impose voltage on a single ended signal.
Signal passing from one board to another are subject to the local ground disturbance.
We can counteract many of these effect by adding more ground.
As frequencies increase beyond 1GHz, 80% of the signal will be lost.
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