NEW PROJECT: Sick of Beige standard PCB sizes v1.0

in PCBs by DP | 0 comments

Are you sick of beige project boxes that hide your cool board and hard work? Wouldn’t it be cool if your project was case ready from the first revision?

We worked with case designer David Moberly (dsm) to create a case-friendly PCB footprint for all our projects. We call the specification Sick of Beige v1.0. Just drop a Sick of Beige PCB symbol on an Eagle schematic to get a board with nice rounded edges, mounting holes, and recommendations for connector placement.

The PCB templates come in two shapes, sized to fit the free version of Eagle and the various inexpensive PCB services. Read on for the full specification, or grab the library and get started with standard boards today.

Full specifications for our new standard boards follows. All feedback is welcome.

List of sizes

Square boards range from 30mm to 80mm in 10mm increments. Bigger sizes are certainly possible, but we’re working with the free version of Eagle in mind.

Rectangular boards use the golden ratio to determine the short side. DP10080 is not a Golden ratio rectangle, but the maximum Cadsoft Eagle PCB size allowed for users with a free license.

PCB templates

Effortless case fits that work the first time. Just drop a Sick of Beige PCB template on an Eagle schematic to get an optimized board that’s ready to fit a case. Grab the library for Cadsoft Eagle below, other formats coming soon.

Cases
There’s a growing number of cases that fit the Sick of Beige v1.0 specification.

SoB v1.0 at a glance

Designing for cases is never easy, but the standardized footprints take the effort out of following these recommendations.

Key values

  • PCBs have 4mm corner radius
  • 3.2mm mounting holes, 4mm from center of hole to edge of PCB
  • minimum 6mm keepout around mounting hole to leave room for standoffs
  • minimum 1.7mm edge keepout for case clearance

Other notes for case designers

  • we see PCB widths vary up to +0.4mm, and recommend you design for up to +0.4mm of extra PCB in both directions

Key values

Corner radius
PCBs have 4mm corner radius.

Mounting holes
3.2mm mounting holes in four corners, 4mm from center of hole to edge of PCB. These will fit 3mm (M3) screws and standoffs.

We recommend minimum 6mm keepout around mounting hole to leave room for the standoffs. Traces routed here might be damaged by case mounting hardware.

Our Eagle footprint includes a 3mm radius 41 tRestrict and 42 bRestrict with its center on each 4 holes, and additional corner keepouts.

Edge keepout
We recommend minimum 1.7mm edge keepout for case clearance. Some cases may use rails, fingers, or bumps to hold the PCB in place by the edge. Components closer than 1.7mm may interfere with the mounting mechanism.

Our Eagle footprints include  a 1.7mm width 39 tkeepout and 40 bkeepout around the board edges.

Reference markings
Our Eagle PCB footprints have other reference markings we found handy.

Center line
A center line makes it easy to align connectors.

The line is on layer 49 Reference, so it will ”’not”’ normally be on the final PCB.

USB-MINIB placement
A cross 5.25mm from the edge marks the correct placement for the USB-MINIB connector in our part library.

The line is on layer 49 Reference, so it will ”’not”’ normally be on the final PCB.

Board size
The board size in the format DPXXYY_v1 is included on the back in the lower right. The text is 1.27mm size, 12% ratio.

This is on layer 26 bNames, and ”’will”’ usually appear on the final PCB.

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