PCB is printed circuit board,it mechanically supports and electrically connects electronic components using conductive tracks,pads and other features etched from copper sheets laminated onto a non-conductive substrate,achieve electronic components automated assembly,welding,inspection,guaranteed the quality of electronic devices,improved productivity and reduced the cost,it’s favorable for repair.
PCB from single layer to multilayer,flex,keep ourselves
PCB industry is technology-intensive,capital-intensive,labor-intensive industry.A middle scale factory have thousands workers, most of automatic machines need worker pile line operation.This years Chinese government impel corporation upgrade the structure of industry and the new labor contract law implement,lead to PCB factory face labor cost raise sharply and shortage,then impact production plan,products
PCB design and manufacture is critical and don’t allowed any mistake.The article will analyses why occurs rough unshaped welding in PCB assembly.
There have many factors lead to rough unshaped welding,like PCB PTH weldability, welding temperature incorrect,solder components incorrect,etc. It’s unfavourable for PCB components running,so we must avoid rough unshaped welding.
PCB PTH
As a PCB manufacture engineer, we saw many PCB designers didn’t considered the produce feasible lead to PCB fabrication cost be raised a lot and they didn’t realized. As most of PCB designers don’t have knowledge of PCB manufacture and don’t know how to optimize design can save money.
Seven tips
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
