PCB Design

It is in everyone's interest that all parts of pre-production and PCB-fabrication go smoothly. "Design for Manufacturability" will help us to minimize the total costs in the process.
At the bottom of this page, you will find links to Organizations, which describe in detail, the rules for PCB-design. It is our experience that designers are familiar with these rules and therefore we will limit this part to a few items that we would like to highlight.

PCB DOCUMENTATION

A good PCB documentation minimizes the risk of misunderstandings and it should contain:

A comprehensive and detailed PCB-specification.

Dimensioned mechanical drawings in Gerber, HPGL, DXF, PDF or PostScript-formats. When applicable, a panel drawing shall be provided as well.

Gerber-files as Extended Gerber or with a consistent aperture-wheel. Avoid drawn pads - use flashed pads.

Artwork can be E-mailed to PRI-DANA.

BASE MATERIAL - FORMATS

The base material is the most costly single component when producing PCB's. To achieve optimal cost savings it is in the interest of PRI-DANA as well as the customer to minimize the waste of the base material. Savings can be done in the designing phase by paying attention to the PRI-DANA standard formats. Contact us for further information about the formats.

PCB PATTERN

It is recommended that the pattern is balanced by cross-hatching to obtain a uniform pattern-density on each side and on opposite sides. By doing this we will achieve a more uniform plating and less warp and twist.

HOLES

PT-holes are always drilled larger than the specified hole size to allow for plating buildup. Be aware of this fact when determining the sizes of the solder pads and clearance. For fixing the PCB during electrical test, it is necessary with at least two NPT-holes drilled in the first drilling operation together with the holes to be plated. The optimal size is 3,2 mm but other sizes are usable. The holes can be placed in a panel-frame.

SOLDER MASKS

At PRI-DANA, soldermasks are registered by very precise optical exposure equipment. A minimal displacement cannot always be avoided, so a clearance of 0,06 mm minimum between the pad and the opening's edge is needed. Strings of mask between pads shall have a width of 0,08 mm minimum. If this is not possible, the strings should be removed.

COMPONENT NOTATION

The component notation is performed by a serigrafical process and it is therefore necessary to keep a minimum distance of 0,20 mm, from the component notation to the pads.

ROUTING

The preferred router bit has a diameter of 2,4 mm. Consider this when panelizing the PCB's.

This was just a brief extract of the situations where we more often see possibilities to ease the process and with that, reducing costs by manufacturing of the PCB's.
Further rules and tips on PCB-design can be obtained at PERFAG, MQS or IPC.
If the PCB's shall be UL-recognized, there are special requirements that shall be fulfilled. Read more about this in "UL-recognition"
At PRI-DANA we will very often be able to produce tighter tolerances than stated in various standards. Contact us for further information.