Screaming Circuits

There is a four step process to complete a kitted prototype pcb assembly order on our website. Registration is required if you are not a member. Please read our Terms and Conditions first.

The steps of the kitted prototype pcb assembly process are as follows:

You may view the status of your prototype pcb assembly order at any time by visiting your My Account page.

Check out our Kitted Order Checklist document (PDF). Box up your kit as described there.

Please only put the kit for one job in a box. If you put parts for more than one job in the same box, we will have to separate them and that may cause delays and incur extra charges. This means that everything with the same order number goes in one kit - parts for ten boards on the same order go into the same kit, but if it has a different order number, it goes in a different kit.

1. If parts or boards are being drop-shipped from another company, make sure they put your Screaming Circuits order number on the packing slip.
2. If possible, keep your parts in the anti-static packaging and moisture-proof packaging that they came in (don't tape the parts strips to anything).
3. Make sure all of your parts are clearly labeled and that the labels match what you put in the BOM that you emailed to us.
4. Print out the Screaming Circuits box label. There is a link to it on your My Account page and on the confirmation email you received. This label has our address and your order number pre-printed.

Then send us your kit, have a soda and eagerly await the return of your assembled pcbs.

Files we need for your pcb proto assembly order:

Please combine the following files into a single .Zip file. Then send it to us during the order processes or email it to files@screamingcircuits.com. Make sure you put your order number in the subject field. Say: “Files for order ####-####”.

Bill Of Materials - in Microsoft Excel format. Please highlight in red any components we will not be placing, or any parts that are not included in the kit.  BOM should include:

• Quantity of that part number
• Reference designator
• Part number (Digi-Key part numbers are okay)
• Part description
• Package description (QFN32, SOIC, 0805, etc. package is very helpful but not required).
• Type (smt, fine-pitch, etc. Type is very helpful but not required).

View our Sample BOM File in Excel format to see how we like it.

BOM for Turn-Key order - For Turn-Key orders, the BOM also needs to contain the part Manufacturer's name and the Manufacturer's part number. Again, Digi-Key part numbers will meet this requirement. View Sample Turn-Key BOM file in Excel format.

Gerbers- Please send us all gerber files generated by your CAD program in RS-274X, as if you were sending them for pcb fab. At a minimum we need silkscreen, solder paste (or stencil) layers for assembly.

Centroid data (aka Insertion or Pick-and-place or XY data) - This is the machine file, which should include: X, Y, Theta, Side of Board (Top or Bottom), and Reference Designator.  If you cannot generate this file, Screaming Circuits can generate it for you from the gerber files for an extra charge. View Sample File. Eagle CAD users see below for a ULP to generate the Centroid file.

Assembly Drawings, instructions or photos - Are not required for assembly, but they do help to ensure all special PCB Assembly instructions are carried out properly.

• If you are requesting any non-standard processes or have ambiguous placements on your board, then we may require assembly instructions or drawings for those parts of the job.

Please only put the kit for one job in a box. If you put parts for more than one job in the same box, we will have to separate them and that may cause delays and incur extra charges.

This means that it all has to have the same order number. Regardless of the number of boards, if they are on the same order, they go into the same kit. If they go to a different order number, they go in a separate kit.

Components - With our patented plate-feed process, we can place parts on cut tape of any length so there is no need to buy reels.

• Please send 5 extra minimum (or 5%, whichever is more) for discrete parts larger than 0201 passives.
• When sending 0201 parts, include 50% extra to compensate for the higher level of attrition with these parts.
• For ICs, QFPs and BGAs we ask for 1 extra per order.
• PCBs – Please have a silkscreen which indicates polarity and 1st-pin markings.
  PCBs, Lead-Free - We ask for an extra PCB and an extra set of the heat-critical components (actual or dummy parts) on lead-free orders to ensure proper oven reflow temperature profiling.

If possible, keep your parts in the anti-static packaging and moisture-proof packaging that they came in.

Don't tape the parts strips to anything. It is better to have the strips loose in the box then to have them taped to a piece of paper or cardboard. Taping them can damage the strips and make them unusable by our machines.

Note that if you send us non-functioning components or pcbs in your kit, we are not liable for repair, rework or replacement of the assembly or components. We strongly recommend that your boards be electrically tested at the board fab house and have complete solder mask and silk screen. 

1. We see your order within minutes after you submit it.
2. We confirm the necessary files and order details.
3. Credit card is charged upon confirmation of your order.
4. We program our machines from the BOM and Centroid file, before materials arrive.
5. Materials are received in. Materials are typically audited the day before your job is run.
6. If all materials are in before noon, the assembly clock starts that day. If after noon, the clock starts the next day
7. A solder stencil and stencil printer are used to mechanically apply the paste.
8. Standard No-Clean Leaded paste is used (Lead-Free processing is also available).
9. Our machine places the SMT components.
10. 9-zone oven is used to reflow solder on SMT components.
11. BGA / Leadless IC components are X-rayed to verify placement accuracy and to detect any solder bridges.
12. Thru-hole parts are added by hand. They may also be wave soldered depending on the board layout.
13. Final Quality Check is performed.
14. We ship the finished PC board assemblies and all extra materials back to you.

Creating a Centroid file from Eagle CAD

This Eagle CAD User Language Program (ULP) creates the specific format surface mount XY location file, called a Centroid file, required by Screaming Circuits for prototype assembly. Download this file (Centroid_ScreamingCircuits_smd.zip) and unzip it into the “ulp” directory inside your Eagle directory.

Then, once your design is complete, simply run this ULP and include the generated file “<project-name> centroid.csv” in the zip file containing your BOM and Gerbers when you order prototype pcb assembly from Screaming Circuits.