Taiwan PCBs

DEFAULT STACK-UP

BOARD OUTLINES

The standard tolerance is +/- 0.1mm

We rout to your board size using the center of the board outline.
Your printed circuit board outline does not have to be square or rectangular. You can submit round boards or boards with a complex shape. Our requirement is that we can convert your outline to a continuous unbroken path. By default, we will rout your board outline with a 0.0625" diameter rout bit. This will result in a minimum radius of approximately 0.032" on inside corners. If your design contains inside corners with radii of less than 0.032", then we will use a 0.03125" diameter rout tool to cut out your board. In this case, inside corners will have a minimum radius of 0.016".

Tighter tolerances are available upon request.

ROUTING

The default rout tool diameter is 0.03" ( 0.7mm)
All features are cut out using this tool if possible (both internal features and the board outline). Smaller diameters are available upon request.

INTERNAL CUTOUTS

For plated slots, the minimum width is 0.016".
For non-plated slots, the minimum width is 0.016".

Your design can have both plated and non-plated internal cutouts. We suggest that you add one layer for each type of cutout (plated or non-plated). Just place elements in these layers that are the exact shape of the cutout that you want. For example, if you want a 0.050" x 1.00" slot cutout of the board, then just add a trace of this size to the appropriate layer. If you have a more complex shape, then just submit it as one or more polygons that describe the edge of the cutout. We suggest you draw the polygon with an "F-Type" shape (a line of zero width). If you choose, you can draw the polygons with any width trace. We assume that the centerline of the trace describes the edge of your internal cutout. Plated cutouts will have the inside of the cutout plated with the finish that you choose (Tin/Lead HASL or ENIG (Immersion Gold)). Non-plated cutouts will not have any plating on the internal edges. Name your plated cutouts layer "PlatedInternalRouts". Name your non-plated internal routs "NonPlatedInternalRouts". If you wish, you can also supply a drawing that details the internal cutouts and we will create the needed geometry for you.

SOLDER MASK SWELL

This is the expansion of mask relief over pad area. Our minimum is 0.004” over pad dimension or 0.002” each side. PCB Unlimited will modify files to meet the minimum dimension. When manufacturing your prototype circuit boards, there may be a small misregistration between the solder mask layers and the underlying copper layers. As a result, we recommend that you swell your solder mask layer so that it is 0.004” (0.002” on a side) larger than the underlying copper elements. This way, if there is a misregistration, then your copper pads will not have any solder mask on them. You should also ensure that your design has a "Minimum Web" of at least 0.003" between adjacent pads. Smart DFM can pinpoint any problem areas for you.

SILKSCREEN

We recommend that your silk screen features have a width of at least 0.005", although the absolute minimum for clear legibility is 0.003". If you submit Gerber data or a .bin ViewMate file to us, then we will modify your silk screen layers if any features are less than 0.005". If possible, we will set all features so that the minimum trace width is 0.005". Where this is impractical, we will reduce the silk screen feature size to a minimum of0.003".

COPPER TRACE WIDTH/SPACING

This is the minimum air gap between any two adjacent copper features. Trace width is the minimum width of a copper feature, usually traces.
For trace width/spacing, we require a minimum of 0.005” for 1 oz. finished copper weight on outer layers. Premiums are added for trace/space specs less than 0.008”
For 1 oz. finished copper weight (inner layers), minimum trace width/space is 0.004"
For 2 oz. finished copper weight (inner & outer), minimum trace width/space is 0.006"
For 3 oz. finished copper weight (inner & outer), minimum trace width/space is 0.008"
For 4 oz. finished copper weight (inner & outer), minimum trace width/space is 0.012

CONDUCTOR WIDTH

+/- 20%

MINIMUM ANNULAR RING

The minimum annular ring on vias is 0.004" (4 mils) each side of the hole. The pad must be large enough to tent over the hole otherwise you may lose the metal in the hole during outer layer etching resulting in plating voids.

FINISH THICKNESS

Overall thickness tolerance is +/- 10% (The overall thickness is greater than 0.040")
Overall thickness tolerance is +/- 0.004”(The overall thickness is less than 0.040")
Minimum finished thickness for 2-layer: 0.012”
Minimum finished thickness for 4-layers: 0.016”
Minimum finished thickness for 6-layers: 0.024”
Minimum finished thickness for 8-layers: 0.040”
Minimum finished thickness for 10-layers: 0.047”

Note: we assumed the copper weight on each layer is 1oz.

HOLES SIZES

Any hole size between 0.004" and 0.250"