More Fun File Facts: ODB++

In my last post, I wrote about the up and coming IPC-2581 PCB manufacturing file format. While IPC-2581 may be looked at by PCB fabricators and assemblers as a holy grail of sorts, it’s not yet widely adopted by CAD software. But, that doesn’t mean that Gerbers are the only option.

ODB++ was developed by Valor in the waning years of the last century as an improved method for getting manufacturing data into their CAM systems. Valor and, hence, ODB++ was purchased by Mentor Graphics in 2010. ODB++ is still widely available, however there’s concern in some circles that it’s not truly open. That concern is where IPC-2581 came from. In fact, IPC-2581 is somewhat derivative of ODB++.

I can see how a CAD software developer might fear the use of something owned by a rival. However, my understanding is that Mentor does it’s best to treat it like an open standard and has made it available more or less as though it is open.

The history isn’t really important. What is important is that ODB++ is a more complete format than the Gerber and is widely supported. Pretty much everything good that I said about IPC-2581 in my prior post also applies to ODB++.

The bottom line is that, regardless of whether Screaming Circuits is your fab (through our partner Sunstone) and assembly (through our factory right here) provider, ODB++ is a good thing. It makes the job easier and more accurate than does use of Gerber files. Both “easier” and “more accurate” help keep costs down and keep ambiguities to a minimum. As you know, ambiguity is the bitter enemy of both accuracy and quality.

Unfortunately, for all of you Eagle users, Eagle does not yet support ODB++. If anyone out there is really good with Eagle ULP scripting, you might want to create a on ODB++ and/or IPC-2581 creation ULP.

Duane Benson
I was ionized, but I’m better now. 

http://blog.screamingcircuits.com/

CAD Data Files

I’ve spent a fair amount of time researching and writing about the centroid file and about CAD library footprints. One of the challenges in this industry is that somethings that are “standard” really aren’t all that standard. That’s why we emphasize following IPC guidelines when creating library components.

Well, a few things have changed since we started doing this a decade ago. For one, some of the enhanced manufacturing file formats (as opposed to the 1970’s vintage Gerber format) have become more prevelent. Those new formats are a very good thing.

Most CAD packages can now output either ASCII formatted CAD data or ODB++ format data. Those file formats have all of the data that would otherwise be found in the centroid and Gerber files. They also have more accurate data. If you can get one of those formats out, go ahead and send it to us. We can also take plain old Eagle CAD .brd files. If in doubt send one of these newer files along with the centroid and Gerbers. We’ll use the file with the best data and, we may be able to simplify the file preparation you have to do with future jobs.

And speaking of the Centroid, don’t worry so much about the rotation column in the Centroid file. You can consider rotation to be optional now. You don’t need to check the rotation, nor do you need to remove it.

Duane Benson
Who will win? Godzilla or Centroid? Maybe the Smog Monster?

More Cautionary Tails

I recently wrote about the horrors of LED marking variations. Unfortunately, LEDs aren’t the only place to find inconsistencies in our world. Another part to keep a close eye on is the ubiquitous three-terminal voltage regulator. For just short of a million years, pretty much all three-terminal voltage regulators followed the 78XX convention. Lm7805 convention

It is not completely universal, though. (Is saying “completely universal” repetitive and redundant?) There are some regulators that divert from convention in thru-hole and in SMT form-factors. Despite the overwhelming prevalence of the 74XX pin-out, you may find some parts that dispense with convention and can bite.

Take the LM1085, low drop out (LDO) regulator, for example. It looks, for all intents and purposes, to be a standard TO-220 or TO-263 three-pin regulator. You’d look at it and assume that it’s a direct replacement for any old 75XX series. But, rather than In-Out-Ground, it’s pinned as Ground-Out-In. The LM1117T is the same.

Mismatched SOT-223You might think: “Of course, it’s different, the part numbering doesn’t follow the 74XX number scheme.” That sounds logical until you look at the LM2940. It follows the 74XX pin convention, as does the MIC39100. It’s not the LDO specification that justifies change the pin-out either. The LM2940 is also an LDO.

Unlike the LED polarity issue, this one isn’t as likely to bite you during assembly. The SMT regulators can only go onto the board one way. If your CAD library footprint is correct, it will be assembled correctly. The through-hole can be easily reversed though if your silkscreen isn’t clear. Marking pin 1 on the board (and checking the CAD footprint) is the recommended approach.

Duane Benson
In the land of the insane, only the sane are crazy.

http://blog.screamingcircuits.com/

Predictions for 2013

It’s been awhile since I used this space to make any predictions about the coming months, but the end of the year is always the logical (if cliched) time to do so.

So here goes:

  • The migration of manufacturing to North America will accelerate, and the mainstream media will begin to report that OEMs are also reestablishing internal production lines.
  • Flextronics will buy at least some of RIM.
  • Robots as substitutes for human labor will be heavily hyped but lightly used.
  • Ousted Altium founder Nick Martin will hook on with a budding cloud-based software company and build a PCB CAD tool.
  • At least two new PCB CAD vendors will emerge.
  • Electronics manufacturing companies will end 2013 with less cash in the bank but brighter prospects for the future.

 

 

 

 

Why Not Nick?

Nick Martin, the founder and, until last week, CEO of Altium, is fighting back against the board that tossed him out.

But the real question isn’t whether he will regain his spot atop the CAD tool developer. It’s why the board saw fit to relieve him of his duties in the first place.

Some contend privately that at least one board member wants to sell the company but that Martin, who is the company’s largest shareholder, has been reluctant to go along. If so, pushing him out would mean removing, in part, one big barrier. For its part, the board has publicly stated that the decision to leave was Martin’s — something he vehemently contests, and which seems unlikely on its surface — and that the company has not returned the type of shareholder value the board seeks.

So while it’s true the move to Shanghai coincided with an improved bottom line and a higher share price, it’s also true the stock hasn’t topped $1 in years (chart — the top line = $1; the current price is about 80 cents). No one is getting rich owning Altium right now. If the board is getting antsy, it’s understandable. Whether that merits replacing  Altium’s answer to Steve Jobs — a design visionary who, according to many we’ve spoken with, has always put the technology first — is for the historians to determine.

 

Cadence: All Sync’d Up

Cadence today announced the release of point revisions to both Allegro and OrCAD, continuing its tradition of keeping releases of its major platforms in sync. They show significant upgrades in timing speeds and simulation speeds, respectively, as well as better use of state-of-the-art collaboration tools.

To the latter point, Hemant Shah, the product marketing manager for Allegro, says the point releases are a reflection of changes Cadence sees in the user base. ODMs are evolving to “parallelism,” he told me. “That’s where we learned the EDA tools were not designed for parallelism and needed to be rethought.” As a result, Cadence adopted Microsoft’s SharePoint collaboration tools, giving users a greater control over different versions and WIP design data management.

It was interesting to hear a major software vendor acknowledge that not everything developed in-house would or could be best in class. Likewise, Shah said that the company’s recent acquisition of Sigrity reaffirms the management’s commitment to the PCB space — something its competitors have questioned from time to time.

He added that the future releases leverage Sigrity’s power and SI technology across both the existing platforms and in Sigrity’s standalone products.

Riding High on Design

The herd is riding on the EDA vendors, almost all of which are at or near 52-week high share prices.

In the past week, Cadence, Mentor and Synopsys hit or were trading just pennies off their yearlong highs. National Instruments and Ansys both traded much closer to their highs than their lows. Even Altium closed in on a high, but that’s a bit deceiving because it’s a penny stock and lightly traded on the Australian exchange.

So, is it the investor herd driving up an industry? Or is it a sign that the EDA market, which topped $5 billion for the first time in 2011, is geared up for a sustained run?

 

Missing CAD

Am I the only one concerned that on the recent analysts call with Mentor Graphics, not once were the company’s printed circuit board design tools mentioned?

The conversation, both from the company and the analysts, revolved solely around the company’s semiconductor design and emulation product lines.

If analysts are focused only on the semi side, then that’s how they will value the company. And the company will orient its internal efforts to align with the analysts.

This bears watching.

Remembering Gene Marsh

Gene Marsh, one of the true industry pioneers, has died.

Marsh, as many readers may recall, founded PADS Software, one of the first CAD software developers, in 1977. In fact, he beat Mentor’s, Cadnetix’s and Daisy’s respective founders to the punch by four years. (1981 was a big year for CAD, as it turned out.)

Gene was such a big deal, Printed Circuit Design started an award for software innovation and named it after him.

While Gene has been out of the industry for years, this is still a sad day.

2581 Hits a Milestone

For years one of the hangups for any data transfer format hoping to supplant Gerber has been the lack of independent validations that the output from a given CAD tool could be accurately read in CAM.

That’s why the IPC-2581 Consortium is right to herald today’s announcement of not one four independent validations as a “significant milestone.”

Today the Consortium published a validation matrix showing data output in Cadence Allegro and Zuken CR5000 has been correlated and validated against typical proprietary and multi-file manufacturing formats by Adiva, Wise, EasyLogix and DownStream. Those CAM vendors also are launching viewers — free, in most cases — to help users compare the data themselves.

The Consortium will take its show on the road next week, presenting a paper at Apex and also at the Cadence users group meeting in March. Both events represent an opportune time to question the members on their progress. If you can’t make the conferences, tune in to PCB Chat on Feb. 22, where the members will answer questions in our new online moderated chat forum.