PCB design

1.How to choose PCB material?

 Select the PCB material must meet the balance point between design requirements,the production and cost.The design requirements include electrical and institutions.For example, now widely used material FR4, dielectric loss have a great impact on signal attenuation at some frequency,so it is not suitable.For electricity,please note that whether dielectric constant and dielectric loss is suitable in the designed frequency.

 2.How to avoid high-frequency interference?

 Avoid high-frequency interference is to minimize the interference of high frequency electromagnetic signal,that is,also called crosstalk (Crosstalk).

 3.In high-speed design,how to solve signal integrity problem?

 Signal integrity is usually impedance matching problem.The factors affect impedance matching include signal source and output impEDAnce, traces impedance,characteristics of the load sidetraces and topology architecture.

 4.How to achieve the differential wiring?

 Differential pair cabling have two points need to note:first, the length of the two lines try to be the same.Second,the distance between two lines  remain unchanged, that is remain parallel.

 5.For clock signal line that has only one output, how to achieve differential wiring?

 If  use differential wiring,the signal source and the receiver are also difference signal,then it is meanful.So for only have one output clock signal,can not be used differential wirings.

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