• PCBManufacturing

PCB Manufacturing

Circuit board manufacturing can either be performed by milling (using our LPKF ProtoMat C30/s circuit board mill) or through an external board manufacturer. The former is good for quick, small prototypes or low- to medium-complexity circuit boards (preferably one-sided). External board manufacturers are good for higher-density boards or if surface-mount components are involved (as you can then get soldermask which makes soldering a lot less error-prone).

PCB manufacturing is an entire discipline on its own. Here is a glossary of PCB design and manufacturing terminology that you might encounter, and a picture of a typical, modern PCB (Microsoft XBox) with some notes on interesting features. Also check out the Bookshelf for technical articles on PCB manufacturing.

The PCB Resource Center is a useful web site for people building or ordering PCB's.

Tools

Prior to manufacturing, you must verify your Gerber and Excellon files to verify that they are what you intend.

• GC-Prevue 10.2.2 [12MB] is a great program for viewing your CAM files.

• ViewMate 8.1 [5MB] is another good Gerber viewer.

• CAMTastic! 2000 [5.1MB] is yet another Gerber viewer.

• gerbv is a Linux Gerber viewer.

Many manufacturers will allow you to panelize multiple jobs and submit a single manufacturing job, thereby saving money, while other manufacturers expressly forbid this. Yet other manufacturers will allow panelization but will charge extra. Some manufacturers will panelize jobs for you (sometimes for an extra fee). Commercial versions of the above Gerber viewers (cost several hundred dollars) should also be able to panelize. Otherwise, you can try GerbMerge, a free panelizing program.

Milling

To submit a board for milling, you will have to provide Gerber RS274X files, an Excellon drill file, and board outline file. Make sure you have performed ERC/DRC on your schematic/board using the LPKF design rules (see the Eagle page for the design rules file).

NOTE: Our milling software does not interpret octagons correctly. Before sending your Gerber files, you must edit them (with a text editor) as follows:

• Find the line near the top of the file that begins with 'AMOC'
• Change the number 22.5 near the end of this line to 0.0

Board Manufacturers

Board manufacturers come in very wide varieties of target markets, capabilities, delivery times, and, of course, prices. You should get a quote from at least three manufacturers for comparison on every job. On-line quoting is very common and lets you compare lots of manufacturers.

Manufacturers I Have Used

• Sierra Proto Express has a "no touch" prototype service that includes soldermask, silkscreen, 2 or 4-layer boards, 6/6 design rules, and have pretty good prices for prototyping.

• Advanced Circuits will do multi-layer boards, inspection, electrical test, silkscreen, and solder mask. They have an on-line design-rule checker which is very useful for picking up board errors that can stall the manufacturing process. They also have a special promotion, $33 per board, minimum 4 boards and you get 1 extra board for free (minimum 1 board for ECE students!), panelizing costs $50 extra flat fee for the job, silkscreen and soldermask included. Definitely worth checking out. Their non-promotional product does not have any restriction on pre-panelized jobs.

• BareBonesPCB is actually a business of Advanced Circuits but market themselves as being ultra-cheap. They provide next day shipping of 2-layer boards, FR4, all holes plated, 1 oz. copper, 1/16" thick, no soldermask, no silkscreen, 6mil/6mil rules, all for $0.64 per square inch plus $44 overhead, no minimum order. Note that you also get socked for at least $13 on shipping. Panelizing is allowed.

• E-protos (Precision Technologies) is another alternative, featuring fast turnarounds, 5mil/5mil features, solder mask, and even assembly. Not as cheap as other places for prototypes, but quite cheap in quantity.

• AP Circuits is a reliable manufacturer that we have used many times. They have 8mil design features, through-hole plated double-sided boards, no silkscreen or mask, panelization allowed. Their P1 prototype service can have boards in your hands within two or three days for about US$70 (for two boards, which is the minimum order). Their cost structure doesn't scale well, however, for larger quantities or for many different drill sizes. BareBonesPCB seems to be a better choice in most cases as the price is about the same and you have a much wider choice of drill sizes.

• Imagineering Inc. has a cheap introductory offer for new clients: $25/board with no minimum quantity.

• Murrietta Circuits will do all of the above and also component assembly. I've had good experiences with them for larger projects (I don't think they're oriented towards prototyping).

• Gold Phoenix is another overseas manufacturer with inexpensive prices and also offers PCB assembly. I would use them again for PCB manufacturing, but not for assembly.

• Myro PCB is an off-shore (Chinese) manufacturer with 6mil/6mil design rules, 14mil holes and pretty cheap prices. Quality and customer service is pretty good, but on-time delivery is poor. Count on orders being shipped as much as 2 weeks late.

Manufacturers I Have Not Used

• Sunstone Circuits has both full-featured PCB's as well as a ValueProto option that competes with Advanced Circuits' $33-each deals. They claim $28/board in small quantities, have 7mil/7mil design rules with 16mil holes, and have a set of 24 drill sizes that you must use. PCB's ship within 2 weeks.

• Futurlec sells electronic components but also does PCB manufacturing and assembly. Their manufacturing is very inexpensive but fairly low tech: maximum 2-layer boards, 10/10 mil design rules, 28 mil via holes with 50 mil pads, 24 mil minimum drill size.

• Quick Turn Circuits does quick-turn prototype boards for (reputedly) lower prices than others. No on-line quoting.

• K&F Electronics, Inc., in Fraser, MI! It's worth asking for a quote.

• BatchPCB is an aggregator for hobbyists. They charge $10 setup plus $2.50 per square inch, with silkscreen and soldermask, 8/8 design rules, no minimum order! Turnaround is slow, as they submit a single combined job once a week to China, receive the combined panels a week later, then re-ship the broken-out boards to customers. It can take as long as three weeks, but it is pretty cheap!

• Olimex is a Bulgarian manufacturer that has low prices (cheap eastern European labor!) They have no problem with panelized jobs (which must have jobs spaced at EXACTLY 10mil), and will do 8mil/8mil boards in 15 days and 10mil/10mil boards in 5 days (plus delivery time which can be as long as 15 days on top of that). Many hobbyists have used Olimex in the past with good results. I've had two e-mail exchanges with them so far for quotations and was treated somewhat rudely in both.

• PCBPro.com has 6mil/6mil design rules, multiple layers, soldermask, silkscreen, electrical test, etc. but not as cheap as prototype houses. Their prototype business, PCBexpress.com has slightly lower prices, but not as low as others. They all seem to be a part of Sunstone Circuits. It's all very confusing.

• PCBFABEXPRESS is a unique service in that they are not a manufacturer but an aggregator. They put together multiple jobs from different people into single, large jobs which they then subcontract to manufacturers, using their spare capacity. You may want to check them out. No panelization allowed.

• EzPCB (a.k.a. Beijing Draco Electronics) is a Chinese manufacturer who will ship five <100sq.cm. boards for $50 for the lot...that's pretty cheap. Their design rules require 8mil features for this price. Watch out for the shipping price, though, as you will have to trade off shipping cost against delivery time. They also do fairly cheap PCB assembly. They take credit cards and PayPal.

• Hughes Circuits is an advanced manufacturer with a wide variety of materials and options, 3mil/3mil design rules, and you know it won't be cheap.

• Accurate Circuit Engineering is another advanced manufacturer with 3mil/3mil design rules and a wide variety of processing/fabrication options.

• Arezen is another off-shore manufacturer, in Taiwan, meaning they'll probably be fairly cheap.

• E-TekNet has 5mil/5mil design rules and look like they have pretty low prices.

• Precision Circuits is a fairly full-service manufacturer with 5mil/5mil rules, a variety of materials and fabrication options, etc. They tend to lean more towards larger runs, e.g., a special on 50 pcs. for $395 (which is pretty good!)

• MPCS has 3mil/3mil design rules and a wide variety of processing options.

• CircuitsWest has 4mil/4mil design rules, but not too cheap for prototypes.

• Pad2Pad is unique (for now) in that they have custom software that allows you to draw your design, route it (manually), then submit it for manufacture and assembly! Several discrete components are available, the rest you'll have to solder on your own. It looks like they are trying to accomplish one-stop web-based PCB construction in the same way that their sister site eMachineShop is providing web-based mechanical component construction.

• Accutrace does both PCB fabrication and assembly. No more detailed information is available as they make you register to get to just about anywhere on their site.

• Online Electronics says they have low prices, but it's kinda hard to figure it out from their web site. No panelization allowed.

• Printed Circuits Corp. has 4/mil/4mil design rules, a wide variety of processing options, and will also do assembly.

• Roca Circuits will ship two 2-layer boards in 3 days for about $230 with 8mil features, 12mil holes, silkscreen (one side), and soldermask. Their full-featured service has 4mil features, 8 mil holes, and up to 24 layers.

• PCBCART is an overseas manufacturer with fairly inexpensive prices for volume production.

• PCBex.com offers $10/board for 2-layer boards and $28/board for 4-layer boards with a 5 board minimum order, 7/7 design rules, 15 mil holes, soldermask both sides, silkscreen top layer only.

• Electropac is not oriented towards hobbyists but has a wide range of capabilities, 4/4 mil features, 4 oz. copper, 8 mil holes, etc.

• Select Circuits has 4/4 mil design rules, 7 mil holes, and a wide variety of processing options. No on-line quoting.

• ExPlus is an off-shore manufacturer with 3/3 design rules, 6 mil holes, and also does assembly.

• NanJing XiLun Electronic Co. has 4/4 design rules, 8 mil holes, and also does assembly.

• Saturn Electronics in Romulus, MI seems to be full-service shop that also does prototypes.

• SpeedyPCB is a Canadian manufacturer with 5/5 design rules, 0.2mm holes, and also does flex circuits and photoplotting.

• Calumet Electronics manufactures up to 12-layer boards with 3/3 design rules and 0.01" holes. Located in the UP, way up near Portage!

• MicrogroupPCB is a USA representative for a Chinese manufacturer that advertises 3/3 design rules and 0.008" holes.

• CSI Electronics in Kokomo, Indiana does PCB manufacturing, assembly, product design support, cable assembly, box builds, etc.

• Silver Circuits (formerly CustomPCB) is based in Malaysia and specializes in prototypes and low-volume production of PCB's and assembly. Their prices are pretty low but their specs are kinda loose: 8/8mil design rules, 24mil holes, 500-hole 10-tool limit, etc.

• FLYPCB is an off-shore manufacturer that seems capable of handling some production logistics beyond just prototyping.

• Cirrex International does PCB fabrication and assembly.

• Infiniteq Assembly focuses on PCB assembly but also provides PCB fabrication with 3/3 design rules, 8 mil holes, and a variety of processing options.

• Crimp Circuits has 5/5 design rules and 13 mil holes. They are located in Toronto with an office in Williamsburg, MI.

• South Bay Circuits has a wide variety of processing options and handles bare PCB's as well as value-added services like assembly, testing, backplanes, etc.

• Fine Circuits supports 4/4 design rules, 8 mil holes, and 8 oz. copper(!), along with a wide variety of processing options.

• Jet PCB offers 6/6 design rules, 20 mil holes, and a $29.99/board special including soldermask and silkscreen (but with $38 shipping). More interesting is their $79.99/board and $99.99/board specials on 4-layer and 6-layer boards.

Here is a web page with links to many of the same companies listed above and the author's opinions.