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As you work on electrical projects, you will typically make initial rough prototypes with a protoboard and point-to-point wiring. As the fidelity of your prototypes improves, you will want to move to custom circuit boards.

The Electrical Engineering shop has the capability of making two-sided circuit boards routed from copper-clad fiberglass material. These boards are very inexpensive to make and can be made in less than a day. However, these boards can be very difficult to populate, because solder bridges are very common during soldering. Especially for close-pitch boards, you will likely be better served to have your boards made commercially.

A number of commercial board-making facilities will make custom prototype boards quickly and at a very reasonable price. These boards are commercial quality, with plated holes, solder masks, and silkscreened information. Often you can get boards made within a week at a cost of about a dollar per square inch. Populating these boards is much easier, because all the traces where no solder is expected are covered with a solder resist layer.

We strongly recommend that Capstone teams use commercial circuit boards. If your boards use small components or are densely packed, you may wish to order commercially-populated circuit boards, although those are relatively expensive. The time savings may be worth it.

In designing your PCBs, please pay attention to the trace widths used for your board. Traces supplying power are typically wider than those used to carry signals. Try and not run traces too close together. Note: plan on at least two iterations of your board. Experience suggests that you should order your board as early as possible to give yourself time to debug and fix it.

Before contacting a company about providing a custom PCB, please contact the Capstone office to discuss your board ordering options. We recommend running your design past the ECEn shop staff before sending in your order.

This document will be updated regularly as PCB ordering options change.

The following are common sources for custom boards. If you know of another source, please let the Capstone office know. We will be happy to add the information here.

1. OSHPark: Makes prototype boards in under two weeks in the USA. Three boards delivered per order; two-layer boards are $5.00 per square inch; four-layer boards are $10.00 per square inch. Website has helpful design information. OSHPark is the Capstone-recommended board vendor. They provide high-quality boards with a minimum of difficulty.
   
   
2. Advanced Circuits: US PCB house that offers instant quotes and provides discounted student rates for 2 and 4 layer PCBs. Also provides their own free PCB layout software. 2 layer quick turn PCBS are $33 each for up to 60 square inches.

Chinese board houses typically offer very low prices, but they also tend to be harder to work with. In many cases there is also a substantial shipping delay. We recommend that you not use Chinese board houses unless you have experience with a particular house and are confident that they will provide the board without problems.

1. JLCPCB : Custom PCBs. 5 pieces of 100mmx100 mm two-sided boards cost $2.00 and are built in 24 hours. A stencil up of 190mm x 290mm is $7.00. Assembly also available. Ship with DHL or UPS Worldwide Saver.
   
   
2. PCBWay: PCB house in China with worldwide shipping. 10 pieces of 2-layer boards cost $5.00 with a two-day build time. Solder stencils can be orderd with PCB boards. Boards can also be ordered with assembly. Shipping via DHL is claimed at 3-7 business days.
   
   
3. Seeed: Low cost special order board manufacturer shipping from Hong Kong. Quoted production time is 5-6 working days. 4 inch square board, quantity of 10, is $4.90. Seeed also offers solder paste stencils and board population.
   
   
4. Elecrow: Custom PCBs. 5 pieces of 100mm x 100mm two-sided boards cost $4.90 and will be produced in 4-7 working days. Air mail shipping is quoted at 7 to 25 days.

For complicated, high-density, small-component boards, you may wish to order your boards commercially populated.

For populating the boards, it can be nice to use solder paste (applied at room temperature) followed by placing parts with tweezers, then reflowing the solder.

This can be done with either a syringe of paste (one pad at a time) or by means of a stencil (place it over the board, and smear paste through the holes in the stencil).

Here's a tutorial on using stencils to apply solder: Sparkfun Solder Tutorial

For through-hole components and connectors, soldering will usually be done by hand. Carefully inspect your connections for cold joints, solder bridges, lack of solder, and other soldering defects.

Here are some sources of stencils.

1. OSH Stencils: Plastic (polyimide) stencils at $0.75 per square inch or less. Stainless steel stencils at $1.45 per square inch or less. Also a variety of technical help about stencils. They claim shipping within 24 hours, weekends and holidays excluded.
   
   
2. PCB Unlimited: Stainless steel stencils at $5.00 per square inch. Also sell prototype PCBs at $1.65 per square inch for a two-layer board, with an 8-day lead time.
   
   
3. Seeed: Metal stencils (probably stainless steel) for $10.00 each (28×38 cm). Can be purchased at the same time as a PCB.

To order PCBs for your Capstone project, complete a Capstone Order Request as described in Orders. Email your PCB files to byucapstone.byu.edu. The Capstone office will then place the order for the boards.

If you wish to be present when the order is placed (so you can answer any questions that may come up), please indicate this in the comments for the order. Then call the Capstone office at 801-422-4847 to arrange a time that works for both you and the office.

The Capstone office will order PCBs on the Capstone office account, rather than on any student's individual account.