Our ISO 9002 standards specify our boards must conform to IPC-A-600 Class 2.
How can I transmit files to Omni Circuit Boards?
Use our file upload form at right. Always PK Zip (.zip) your files into a single file. It's efficient and keeps your files intact.
What files are needed?
We need a gerber file for each copper layer, each solder mask, and silkcreen. One of the gerber files should have a board outline. A PCB fabrication drawing is helpful, though not necessary. We also need the aperture information associated with each gerber file. We recommend, but do not require, RS274X format. This format has the aperture information embedded into the gerber file itself.
We also need an excellon drill file and the associated tool sizes.
Finally, if a readme.txt file containing all important information is not yet industry standard, then it should be. A good example of a readme.txt file can be found here.
What is the deadline to get a job going?
We need to have complete job files and authority to proceed, usually in the form of a purchase order or prepaid authorization, by 10:00 AM Pacific (PST) time for that day to count as working day for the board production. So, if we have files and a go-ahead for a 5 day turn by 10 AM Monday morning, the boards would be ready by end of the day on the following Friday. This is for turns of 5 days or more. Weekends do not count as working days.
How does timing for quick turn jobs work?
For quickturn jobs of 5 days or more, see above answer. For turns of less than 5 days, it works on a 24 hour basis, so a 3 day turn would be 72 hours, a 2 day turn 48 hours, and a 1 day turn is 30 hours. If we begin production at 11 AM Monday morning for a 2 day turn, the order should be ready by 11 AM Wednesday morning. Weekends do not count as working days.
Can you reproduce this board?
Sometimes job files for old boards cannot be found, or it was done in the old tape-up days. We can reproduce a board based on a sample only, if it's single or double sided, and if all the parts are removed so we can measure the features. We charge PCB design services by the hour though, so it's usually cheaper to lay it out again. It's only cost effective for simple designs.
What is the minimum annular ring?
We require minimum 0.005" copper pad ring around drill holes. Under ISO 9002 standards, Omni does not recommend a board with a smaller copper ring than this.
What Gerber Data Format?
It is a good idea to tell us your data format for both drill and gerber files in your readme file. Our recommended format is 2.4 leading absolute coordinates for the gerber files, and 2.4 trailing absolute coordinates for the drill file. Set software arcs to "on", vector plotter type, and "no" to G54 data.
What is the finest silkscreen resolution possible?
Our best resolution for the silkcreen layer is 5mil.
What are the minimum Traces & Spaces?
Extra base copper on a board will limit the size of the features on it. The following is a list of the minimum traces and spaces:
| Base Cu / Oz | Traces / mil | Spaces / mil |
|---|
| 0.5 |
4 |
4 |
| 1 |
8 |
8 |
| 2 |
10 |
10 |
We may be able to go below these guidelines under some circumstances, depending on the layout of the board.
What is silkscreen clipping? Does Omni clip silkscreens?
This is when the CAM operator removes all silkscreen elements that would be printed on the pads. Omni only clips the silkscreen on request or when the boards are to be electrically tested.
What does copper thickness: 0.5 + 0.7 Oz Cu mean?
The first number refers to the base copper we start with. The second refers to how much we plate up the board by. So 0.5 + 0.7 Oz would be a little over 1 Oz Copper.
What is the recommended copper thickness?
The thickness of the copper on a board is a design requirement, so Omni cannot make a recommendation on this issue. We can say that most boards we make have 1 Oz finished Cu. In our download section, we have a copy of a small program that replicates the current capacity chart, it may be of some use.
What if I'm designing with AutoCad?
If you are designing a board in AutoCad and don't have the gerber file add-on, you can export the design into HPGL format. We need the plotter type it was written for and the pen width table. We can also import *.dxf files. It is best to save in AutoCAD 12 format and more efficient to use a layout program to design a board, rather than using AutoCad. AutoCAD files have to have the drill file created in CAD, and the layouts are generally not formatted the same way files from layout software would be. Consequently, building from AutoCAD usually has extra editing charges. A freeware layout program is available here. Functional demo software can often do the job, try our links page.
What is the Dieletric Constant of FR4?
The Dieletric Constant of our FR4 is about 4.7 at 1 MHz. However, we cannot give a fixed value for this since it tends to drift from batch to batch. If a fixed dieletric is required, it is possible to build on specialty materials. Omni has experience with Rogers materials, duroid and polyimides.
What is OMNI's credit policy / Can I pay by Credit Card?
Yes, Omni does accept payment by Credit Card and our credit terms are as follows;
- Terms for first order are Cash in Advance (CIA) for orders greater than $500 before we start the order. Future orders may be Cash on Delivery (COD) or Net 30. COD means cash on delivery, receiving payment before the job is released.
- To apply for credit, the customer needs to fill out a Credit Application form. We need three trade references from other suppliers. Rental, Insurance and solicitors are not generally considered trade references.
- It takes up to 5 business days to process a Credit application. Incomplete applications will delay the credit process.
- If credit is not established when the product is ready for shipment, shipping will be held up until credit is approved or payment is received.
- Accounts exceeding the granted credit limit must be paid down immediately or the orders in production will be held up.
- Past due accounts will revert back to COD. The customer needs to pay all overdue accounts and any orders which are in production. There is a 2% service charge on overdue accounts.
- We accept payment by Visa, M/C, Cheque or cash.
There is a $25 service charge for dishonoured cheques.
Can Omni support me with Offshore Sourcing?
Omni Circuit Boards is dedicated to being your preferred source throughout your product development cycle. Our core competency is prototyping and short run production and to meet your needs we have a dedicated production team in-house to ensure you receive support through production and design feedback. And when your production quantities increase we are ready to help with offshore sourcing. Using our industry knowledge and experience we are able to support you through our global partnerships. Our long-term relationships with offshore sourcing which is available in White Tin, HASL and ENIG finishes ensures you receive time sensitive, cost effective and quality assured circuit boards right to your door.
What final finishes can Omni provide?
For prototyping and small volume runs we offer Immersion White Tin, HASL and ENIG finishes with the final processing for the latter two being performed by suppliers we have long standing relationships with. For mid to large volume runs we provide offshore sourcing through our long time suppliers and board finishes are also available in HASL, Immersion White Tin and ENIG.
Can Omni provide a Prototyping, "No-Tooling" service which doesn't require Tooling costs?
Yes, Omni provides a Prototyping service for boards that meet no-tooling standard parameters.
Are the articles Omni published in the past still available?
Yes, over time Omni will be re-publishing the original articles for your reference. You can find them by following this link: Omni Archives.
What storage and handling conditions does Omni recommend for PCBs?
Recommendations for PCB storage and handling can be found by following this link: storage and handling.
Does Omni offer a discount for extended turn deliveries?
Yes, when you request an extended turn Omni provides a 5% discount. Contact us for details..