On the basic single layer PCB, the components are concentrated on one side and the circuits on the other. If multilayer board is to be used, the board needs to be perforated so that the components pin can pass through the board to the other side, so the guide hole will go through the PCB board. So we can see that the pin of the part is soldered on the other side.
At present, many manufacturers use another method of tracing, which is to connect some of the circuits, and it uses buried and blind via technology in the tracing. Blind via is a few layers of internal PCB connect the surface PCB; it does not penetrate the entire circuit board.
The buried via is only connected to the internal PCB, so it is not visible from the surface. Because the blind via does not need to penetrate the whole PCB, if it is six or more layers, the light will not pass through the card against the light source. So there was a very popular saying:to determine four layers and six layers or more of PCB by seeing if the through holes leaking light.This method has its own reason, and it also is not suitable, it may use as a kind of reference method.(pcb manufacturing companies)
Process of pcb manufacturing:
Our Company is UL,ISO9001,ROHS and GJB9001B certified.
Packing and Shipping:
1. How to Get a quotation?
For PCBs,pls send us the Gerber File.For PCBA,pls send us the Gerber file and BOM(Bill of Materials)
2. What is the MOQ?
No MOQ.1 pcs is ok.
3.What is the lead time?
For PCB orders,the lead time is 2 to 10 days.For PCBA orders,the lead time will be 15 to 30 days.
4.Will the boards be tested before shippment?
Yes,all PCBs will be tested by Flying Probe or E-test.For PCBA,we will have AOI,X-ray,and functional test
Email us to get a quote: email@example.com