First look at the main points of the plan
1. Planning of the number of signal layers;
2. Planning of power supply and stratum number.
First, the signal layer number planning method
To plan the number of layers in the signal layer, it is mainly to calculate the wiring channels of each main part.
So what are the specific methods? Let’s take a look.
1. First evaluate the outgoing channel of the main IC part, for example, for BGA
Device design project, considering the depth of the BGA and the PIN spacing of the BGA, go
Plan the number of outlet layers, generally 1.0mm pad pitch and 1.0mm or more pitch
Generally, there can be 2 wires between the vias, 0.8mm pad pitch and one of the following
Only one line can be used between BGA vias. For example, if you have a connector, you need to consider it.
The depth of the connector, you need to consider the number of lines between the two pins to evaluate the line
The number of layers.
2. Evaluate the high-speed signal routing channel on the board, general PCB design
When the high-speed signal line width and line spacing have strict requirements, there are more restrictions,
Consider high-speed, cross-segmentation, STUB line length, line spacing, etc.
The number of channels required for the signal area and the number of wiring layers required.
3. Evaluate the cabling area of the bottleneck area. After the basic layout is processed,
Focus on narrower bottleneck areas. Comprehensive consideration of difference
Line, sensitive signal line, special signal topology, etc. to calculate the bottleneck area
How many lines can be generated in the domain, and how many layers can pass all the required lines through this
The above is the rule method of pcb board design layer, I hope to help you!
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