Introduced in front of right angle alignment and differential traces, today to introduce a serpentine traces. Is a serpentine manner PCB trace trace frequently used design, the main purpose to adjust the delay, the system timing to meet the design requirements.
However, serpentine line to a certain extent corrupted signal quality, transmission delay change, so wiring to be avoided. However, the actual design of the PCB in order to ensure sufficient retention time signal, or reduce the time offset between the signals so that the same group had deliberate winding. When the signal transmission serpentine traces, coupling occurs between the line parallel with each other, as a differential form, the smaller S, Lp greater, the greater the degree of coupling. Transmission delay may lead to reduced quality of the crosstalk signal is greatly reduced.
The following are a few suggestions to the PCB when the processing engineer serpentine line:
1, as far as possible to increase the distance of the parallel line segments (S), at least greater than 3H, H refers to a signal trace distance to the reference plane, is bent around the large traces, As long as S is sufficiently large, almost completely avoid mutual coupling effects.
2, to reduce the coupling length Lp, when Lp twice the delay approaches or exceeds the signal rise time, the crosstalk will be saturated.
3, a signal transmission line strip (Strip-Line) or buried microstrip lines (EmbeddedMicro-strip) due to the serpentine line delay is less than a micro away (Micro-strip). Theoretically, strip line will not affect the transmission rate of differential mode crosstalk.
4, high-speed as well as more stringent requirements on the timing of the signal line, try not to take the serpentine line, especially not on a small scale serpentine traces.
5, can often employed serpentine traces at any angle, such as C structure can effectively reduce the mutual coupling.
6, high-speed PCB design, a so-called serpentine inability filtering or interference, so as to match the timing purposes only.
7, may be considered a spiral manner away for winding wire. More knowledge about the PCB to do in the Czech Republic with the official website www.jiepei.com/g602, welcome to learn together!