PCB Hole opening Window and Hole Cover oil Difference

With regard to the "through hole window" and "through hole cap oil" point (PAD and VIA usage distinction), many customers and design engineers often ask what this means when placing a system order, which option should I choose for my file? This point is explained as follows:

I often encounter such problems, the design is seriously non-standard, it is not clear that it is pad, that is the use of via, sometimes the conductive hole is processed by pad attribute, sometimes the key hole is processed by via attribute, the VIA attribute and PAD attribute design are confused, resulting in wrong processing, which is also one of the problems that often appear complaints. And for the circuit board production factory, in the processing of CAM data, some processing film engineers, because the customer design documents are not standardized, and make mistakes, help customers modify the document, the non-standard design is done, with their own experience to process engineering data, which leads to and contributes to the customer's design is not standardized. Just because you did it right last time doesn't mean your document is right! All engineers must pay attention to the design standards and specifications! Strictly require all processing of film engineers, as far as possible to maintain the status of customer documents! As far as possible, according to the design specifications and standards, can not be processed according to the so-called experience! Reflect the problem, so that you can make a reference to the design engineers, improve the design quality and reduce the occurrence of problems!

This article mainly explains conductive holes, plug-in holes, and the connection between protel /pads/ and geber files, conductive holes: via, plug-in holes: pad especially prone to several problems:

First, via in the conversion process, because the design is not standard or you are not clear about the conversion gerber setting rules, and cause problems when you send the gerber file the factory can not distinguish those are through the hole those are plug-in holes, then the only identification is according to the file processing, which helps the welding layer that there is a window!

The gerber you sent out is the film file, and the factory has no way to check whether it is conductive hole or plug-in hole. Please check the gerber file to see if it is helpful for welding layer. If there is one, open the window, and if there is not, cover the oil.

Two, pad and via mixed use, resulting in problems

1. when your files are pads or protel sent to the factory, requiring the hole cover oil, be careful to note that you have to carefully check whether your plug-in hole (pad) is also useful via, otherwise your plug-in hole will also be green oil resulting in welding.

Contention: The plug-in hole must be the above to spray tin, how do you cover the oil, how do I use, when saying this, please check the file, is it pad design or via design!

2. when your file is protel or pads, send the file to the PCB factory, the order requirement is through the hole cover oil, many customers use pad(plug-in hole) to represent the conductive hole, resulting in your conductive hole to open the window, may you want to be through the hole cover oil, then may be the point of contention is, I want is the conductive hole cover oil, why to open the window? Then please check your file design!

At this point, we explain again as follows, if you are via, press via, if you are pad, press pad! Because no one will know which conductive hole you are, which is the plug-in hole, and via and pad are the only identification, please be clear!

Three, how to design a hole cover oil in protel or pads! This is the most standard practice, if the design standard, you will not go wrong!

There is a tenting option in the via property in protel, if you tick it, it must be covered with oil, then you turn out all covered with oil, in pads, pads transfer file is to think through the hole (via) cover oil method: When exporting soldermask (soldermask), just check the soldermask top -- via below, which means all pass through the window. If you do not check, pass through the hole to cover the oil.

To summarize: pad do according to pad, this is the plug-in hole, via you have two choices, if you provide the original file, let you choose when placing the order, if you provide the gerber file, be sure to check whether the gerber file meets your requirements!