​How to add silk printing to SMT devices in PCB design?

Silk prints on PCB are very common. Silk prints on PCB have many auxiliary functions, such as: indicator product models, board dates, fire retardant ranking, etc as well as some interfaces and jumper marks.

For Non-High-Density boards, we are used to signing the outer frames, first foots, etc. of the components with silk printing, so that we can identify it when do manual soldering or repair.

SMT component device silkprint drawing precautions：

1. SOIC components, in order to avoid silk marks from occupying additional layout space, you should draw the border of the device under the SOIC device and mark the direction of the device.

2. Similar to the QFN flat -free feet packaging device, the wire printing box cannot appear under the component. Because even if the silk printing is small, it has a height. The height of the silk seal plus the height of the welding green oil layer may cause a flat -unspeed foot device such as QFN. Welding phenomenon. As shown below

3. Scenery marks under the surface of non -passive device, such as patch capacitors, chip resistance, patch diodes, etc. In addition to drawing the frames of these surface stickers, you need to draw a logo below the component to distinguish the distinction Is it a patch capacitor or a patch resistance or a diode.

4. Patch components with a size of less than 0603 are not recommended to mark the wire printing below the device. Because the height of the silk printing will affect the welding quality, the printing of the silk print is prone to displacement bias, resulting in the pads of the wire printing, which affects the welding quality.