What is Silkscreen?

Silkscreen is printed on the top/bottom of the PCB with letters, numbers and symbols, the most common silkscreen color is white.

Silkscreen is to facilitate assembly and guide you to better understand the board’s design, in the top and bottom surfaces of the PCB, printing on the logo and text points which you need, such as component labels and nominal values, component outline shape and manufacturer logo, production Date and so on.

pcb board
(This is a board comes from Seeed Studio Fusion service, they offer PCB prototyping and the quality and silkscreen are great, if you want to try your design, it’s a good choice.)

Which layer in Gerber represents the silkscreen?

In Gerber, Topoverlay and Bottomoverlay are the top and the bottom of the layer to print the silkscreen. (You can view the pcb layer in Seeed Studio Fusion Gerber Viewer)

Silkscreen is important for electronic soldering, let’s pay attention to some details.
1.  All components, mounting holes, positioning holes are required to have the corresponding silk label in order to facilitate the installation of PCB board, such as PCB board mounting hole silk screen with H1, H2 … … Hn logo.

2. Reducing the probability of welding reverse, Silkscreen should follow the principle which is from left to right, from bottom to top, for electrolytic capacitors, diodes and other polar devices in each functional unit as far as possible to maintain the same direction.

pcb silkscreen

3. In order to ensure the reliability of the welding device, it requires no screen on component pads; in order to ensure the continuity of tin, tin track requires no screen; in order to facilitate insertion and maintenance of the device, the device should not be obscured by the bit number of the mounting means.

4. Silkscreen better not be put on the vias, holes and pads, so as not to open the welding window caused when part of silk screen lost.

silkscreen
As shown below, the hole printed in the silkscreen “8” and the hole cut the silkscreen, when the board came back, you may be unable to figure out the numbers.

5. Component polar polarity and the direction of the connector should be clearly represented on silkscreen layer, it is easily recognizable mark polarity.

6. The identifier of the device on the PCB must be consistent with the identifier in the BOM list.