PCB ASSEMBLY FAQS

Q: What information (files and data) do I need to send you to confirm pricing and place order?

A: We need the following files for every pcb assembly order:

  1. PCB assembly BOM list (or .xls spreadsheet). The BOM needs reference designators, value, package/decal, description, and part number.
  2. Cad-generated component location XYRS file-also called the parts position/rotation file or the machine pick-n-place file. Each CAD system will generate this, if requested.
  3. Board X,Y, 0,0 reference designators; Board Fiducial Marks are appreciated but not required.
  4. Cad-generated Gerber files for Top/Bottom Copper, Silkscreen, and Solder paste mask. We also need the solder mask file if we're buying the PCBs for you.
Q: In what formats do you accept parts?
A: We gladly accept parts in cut tape, trays, tubes, reels, even bags if necessary...whatever. If you are ordering cut-tape from a vendor please request a continuous strip for the order quantity plus overage. If you drop ship your parts to us please make sure they have our XCO order number with them for identification.
Q: How do you handle Shipping and Handling?
A: We can ship UPS and FedEx as requested. If you have a shipping account already established, please provide that information upon order confirmation and we will bill the shipment charges directly to you. Otherwise, we will prepay and add all shipping charges we've incurred to your invoice upon closing. All packages are sent insured.
Q: How do I pay?
A: Credit card is the easiest (plus you get miles!). We accept Visa, MasterCard, and American Express.
Q: Your online quote calculation is not the firm/final quote. Why not?
A: If your data and design matches the data input to the online price calculator, then it is the same. Often, the initial data we receive is not the final or correct data needed for proper pcb assembly. Things can change with a printed circuit board design as it goes through the design/layout process. Consequently, data files and placement configurations may not be updated or synchronized upon submittal to us. We will also verify the component counts and stuff configurations, fine pitch and line item counts, turn time and board quantity. After reviewing your files, we will send you a formal quote for your final approval and authorization. The quote will include line item detail for pcb assembly costs, set up fees, stencil expenses as necessary, and any promotional discounts currently being offered. We also include complete documentation "deliverables' which you can use to verify both our quote and the integrity of your data. These "deliverables" allow you, the customer, to verify that all information received relates to the same revision of a board and that all is ready for a successful build.
Q: Why do you need the gerbers?

A: For each side having SMT or through-hole components that we will be populating:

  1. Copper - for verification of pad location and scaling.
  2. Paste - for stencil generation.
  3. Silk - for reference designator location and rotation verification.
Q: Why do you need the silkscreen gerber layer?
A: The silkscreen layer normally includes POLARITY information and reference designators for parts. From diodes and polarized caps to QFNs and BGAs, orientation is critical. If your CAD system is 'weak' in calling out the rotation, then the visible information contained in the silk is our best check. That doesn't include the requirements of a repair tech or a QA inspector.
Q: From which CAD systems do you accept data?

A: Our SMT Design and Verification Assembly program includes various specialized .DLLs to aid in importing various CAD program outputs, as well as being able to read generic .csv and .txt files. The only requirement is that the output format is NOT in a binary format. CSV or XLS is very much preferred for both XYRS and the BOM.

We will accept data from almost any CAD program used today. Orcad, Protel, Eagle, Power PCB or Pads, Cam350, and PCAD are examples of the most commonly used, however we welcome the opportunity to develop additional interfaces. Just let us know what you are using.

Q: How many extra parts do you require?
A: Please send a minimum of 50 pieces on a continuous strip 10 to 12 inches long or 5 % overage for all common passives; whichever is greater to avoid any delays in production. IC's and more expensive parts usually require 1-2 extra at most. Parts that are properly shipped in anti-static carriers or in moisture sensitive packaging will be treated with care both while being inventoried and placed. Any unused parts are returned with your job.
Q: OK, worst case scenario... What happens if you receive incorrect components, the wrong number? In other words, you discover shortages.
A: In all cases, our receiving inspection of your parts will be based on our BOM, your packing list, the actual parts, and (if available) the kitting labels! We will contact you as soon as this problem is discovered, which will allow you to drop-ship missing or incorrect components, request that we hold the job, or simply no-stuff/no-load the parts in question.
Q: When does your promised "Turn Time" start?
A: The clock begins when we have your data finalized and approved, and all the necessary parts/boards in-hand to assemble. Remember, we are Prototype and Quick Turn Specialists! Standard turn time for most orders is 5 business days. Data and materials must be received by 10am EST to be counted for that day.
Q: What happens if UPS, FedEX, or DHL is late in delivering my order?
A: We work very hard to make sure all your PCB orders get shipped on time. There are occasions, however, when the freight carriers have delays and/or make shipment errors. We regret when this happens but we cannot be responsible for delays by these carriers.
Q: What files do you need to manufacture my printed circuit board?
A: We require gerber files (274X or 274D with an aperture list), an excellon drill file, and a drill tool list (may be included in excellon drill file). We can use other formats such as ODB++ or AutoCAD dxf to create gerbers for you.
Q: What is Test NRE?
A: The Test NRE is a one-time "non recurring expense" for electrical test. This charge is optional but when paid, all circuit boards will be tested each and every time that part number and revision is ordered without additional charge.
Q: On turn-key jobs, what does PCB Assembly Express do about part crossing or substitutions?
A: PCB Assembly Express holds no inventory, therefore we will not substitute parts on your bill of material with parts we already have. We can suggest crosses or assist with component selection if necessary, but we require customer approval before ordering.
Q: How does PCB Assembly Express order components for Turn-Key orders?
A: We order to your exact bill of material ordering 5% or 5 extra for most components. Occasionally we are faced with minimum / multiple orders where extra components must be purchased. These parts are addressed, and approval received from our customer prior to ordering.
Q: What is the lead time on a turn-key order?

A:

  • Procurement lead time is in addition to assembly lead times quoted on the website.
  • If we order circuit boards, in most cases this is the longest lead time part, and is determined by customer needs.
  • All components must be received prior to beginning the assembly portion of the order