Similarities and differences of differential signal, common mode signal and single ended signal (2022.2.14)

Differential signal : Same size , In the opposite direction （ Half phase difference ）, The receiving end subtracts the two signal lines , Get double amplitude signal . Twisted pair as much as possible , The influence of noise on the two wires is the same . Facilitate long-distance transmission .

Applicable scenario ：can Bus

advantage ：

1. Strong anti-interference ability ： Noise is usually simultaneous 、 Equivalent transmission to the signal line , The difference can be offset .

2. It can suppress electromagnetic interference （EMI）, The electromagnetic interference to the outside is also small .

3. Timing positioning is accurate ： The receiving end of the differential signal is the point where the difference between the signal amplitudes on the two lines jumps , As a judgment logic 0/1 The point of . Single ended signal ： Take the threshold voltage as the signal logic 0/1 Jump point of .

shortcoming ：

1. Large space

Single ended signal ： Most low-frequency level signals are transmitted using single ended signals

advantage ：

1. Small footprint

shortcoming ：

1. Easily disturbed

Common mode signal ： size 、 In the same direction , Transmit interference signals