Ever you touched printed circuit board filed, you will know it is a customized production field. How to supply custom PCB assembly service is the title today we are going to talking. No matter in which field customized job need have drawing firstly, for PCB assembly we also need it, just we call the drawing gerber file, pick&place file and bom list. These are the files we need to finish all the steps.

Do you know how each file work during whole assembly process? Maybe you are engineer knows everything, but not everyone knows it, so let me use this article to introduce how we finish custom PCB assembly with these files.

Firstly is gerber file.

Yes, gerber file is used for bare PCB production, but in assembly step, we also use it to do stencil. Stencil is used for print solder paste onto the bare PCB pad, which they will be assembly with SMD components. The steel mesh requires a steel mesh layer in GERBER, it is indeed very convenient to have this layer as a steel mesh. The steel mesh file in the strict sense is the standard PASTE layer derived from the PCB file. When making a steel mesh, you can directly follow the size and position of the pad on the file, so the paste layer is called the steel mesh layer. Firstly, print solder paste onto PCB, then put it into reflow oven. Multifunctional assembly machine will heat the solder paste to melt it, and all the SMD components will be assembled onto PCB board that time.Stencil

Then is bom list.

What is bom list used for? Bill of Material (BOM), using computer-aided enterprise production management.

First of all, to enable the computer to read the product composition and all the materials involved in the enterprise. In order to facilitate computer identification, the product must be represented, transform the structure into a data format. This file that describes the structure of the product in data format is the bill of materials, which is the BOM. It is the technical file that defines the structure of the product. We need to purchase components based on bom list information . Every electronic PCB board has different components requests, it shows custom meaning. Bom list include components type number, package, quantity and location numbers. To make sure using right components is our responsibility for custom PCB assemble.

bom

Next is PICK&PLACE file

It is used for assembly program making by multifunctional assembly machine. There are components location numbers, the X and Y axes correspond to the distance from the far point .

How to output pick&place file?

Using the function of PCB design software to derive coordinate data. This is the most common method to derive coordinate data. Most factories use this method to obtain coordinate data of components.

The steps can be roughly divided into three steps:
1)unit switching
2) setting coordinate origin
3) coordinate derivation.
The following will introduce some common methods of deriving coordinate data of PCB design software.

pcb board design software

When we discussion assembly someone would like to say SMD , someone would like to say SMT. Actually they have different meanings.

SMT: surface mounted technology, directly mounts the externally attached components and solders them to the assembly orientation of the circuit board PCB.

SMD: Abbreviation for Surface Mounted Devices, which means surface mount device which is one of the SMT components. There are many kinds such as chip resistance, chip capacity, chip transistor, chip inductor and so on.

The SMD is in the form of a rectangular sheet, a cylindrical row or a profile and its welded ends or pins are fabricated in the same plane. They are suitable for the electronic components adhered to the external placement machine. Reflow soldering: Mechanically and electrically connected between the terminal or pin of the external adhesive component and the printed circuit board pad by melting the paste solder paste per-distributed onto the PCB circuit board pad.

As a professional PCB and PCBA Manufacturer, not only we can provide one-stop service from PCB Design, Components Sourcing, PCB Manufacturing and PCB Assembly, but also we have ERP system to manage every project from production file, quotation, purchase, production, delivery until service after it. Every step ERP will show clear and accurate data . Date will be found quickly and precise no matter when client wants to begin project.

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