Back Board Routing Topology
Back board routing topology included Centralized Switching,Distributed Switching,Hybrid Switching,Holst/Slave Switching.
Centralized Switching
Distributed Switching
Hybrid Switching
Host/Slave Switching
The Structure of Back Board
VITA standard required the dimension of back board,tooling hole position and size,direction,each solt,and case heat dissipation etc.
Back Board Connector
Back Board use MULTIGIG RT connector,the
The high in difference of heavy copper PCB is easy lead to oil float away,fake copper exposure,oil uneven when printed solder mask if controlled unwell.This article analysed and improved this problem through line mask printing area, solder mask opening of silkscreen ,printing lay up time and printing method.
The traditional process
Pre-treatment--->solder
Vias is the important constitute of PCB, the cost of drilling fee is 30%-40% of whole PCB cost.
Parasitic capacity of vias
The parasitic capacity exists in vias refer to ground layer. Assume ground layer isolate via diameter is D2, via pad diameter is D1, PCB thickness is T, dielectric constant is
If you open SOC PCB Layout Guide,you can see it mentions high speed signal line’s angle question: high speed signal line don’t layout in right-angle, it should layout in 45 degree angle,and arc is better then 45 degree. How’s the truth? How to design the circuit line? 45 degree or
Follow electronics technology development,many PCBs outline became more and more complexity. New products on market require PCB outline with high accurate,also appearance is criticized.it’s difficult for traditional outline manufacture. As Laser machining have advantages like high accurate,high speed,low cost.more and more PCB manufacturers start to purchase laser equipment to solve
Bubble and overflow glue are common questions of FPC quality.Coverlay flow follow press temperature go up lead to copper pad adhesion glue like epoxy.
The reasons of glue overflow
It involve many aspects,like coverylay protection in process,FPC factory technology parameter,environment protection,worker operation,etc.
One of reasons: Coverlay parameter when making.
When CL is coating and
If the vias is too close to pad, solder will flow out through via when make reflow soldering,lead to false weld.
Countermeasure: Move vias to 0.2mm far away from pad.
This kind of question always happened to PCB design. Engineer had to save space for boards limited by dimension. But it may
Flex-Rigid PCB is mix FPC and Rigid PCB,followed special requirement and press them together. It’s compatible both of FPC and Rigid PCB advantages.Enginner always use 2 rigid PCBs,a flex pcb and a switch to connect them before Flex-Rigid PCB be published.Flex-Rigid PCB have strong resistance for bad application environment,it’s good
Here two PCBs file need to combine one PCB file, it will save much setup fee for prototype.How to build one PCB file with different PCBs in Allegro?
Below is the second PCB.
We create a new PCB module.and select follow the red circle.
Save the module with mdd.then copy the second
It’s important to know factors affecting of PTH throwing power to electronics products, then improve high aspect ratio for facilitating productivity.it’s good for electronics products reliability,reduce fabrication cost,improve productivity.
PTH
Plated through hole(PTH) is the crucial process of PCB manufacture. it need be plated enough copper in wall of hole for connect
