A little extra checking may take a little extra time, but it can save a lot in the end. This sort of thing just bums me out. I’ve done it and similar things a few times myself. I’ve used a library for a connector with the same footprint, but smaller diameter pins than my chosen connector. That was a bummer too.

My best guess is that it’s a 0.1″ (2.54 mm) spaced footprint on the PCB and a 2.5 mm pitch part. It almost works. You might not even notice if it were a three or four pin part. At six, you’d certainly notice and at something from there on, the part simply will not fit.

In a prototype world, you may be able to get away with bending the pins a bit and forcing them a little way in, but maybe not. In a production electronics manufacturing environment, most certainly not.

Duane Benson
In the world according to Google, it’s only 72,000 beard-seconds off.

http://blog.screamingcircuits.com/

I recently received an email comment about my blog writing that I think does a very good job of illustrating one of the frustrations that many design engineers face.

“Please have someone teach Duane the difference between “then” and “than”. It really makes him look dumb, and I very much doubt that Duane is dumb. It’s just painful see these everywhere in his blog. regards“

I’ve also been called out on “it’s” vs. “its.” At least, I seem to mostly have the “to”, “too” and “two” down. Now, I’m a reasonably educated person and writing is a significant part of my job, so you would think that I wouldn’t fall into traps like this. Undeniably, I do. It drives me nuts. I even have a couple of websites that I refer to (when I think about it) to help with such things. Site one and site two, but obviously I still fall into the traps.

So, how does that relate to the frustrations of a design engineer? Well … read my blog. Most of my writing is about a very similar issue. Check this one about via in pad. And this one about parts libraries. Or this one about shorting potential under a QFN.

None of those problems was created by “dumb” people. Likely, all those boards were created by intelligent, highly skilled, well-trained engineers — people who got picked on in school for blowing the curve, or were called “Spock” by kids not on a college track. Yet, what does such an error get? It may get a blog post here. It may get a Twitter comment like this that I wrote about. Of course, some times silly little oversights like this have more dire or more expensive consequences.

And the moral of the story — attention to detail and continuous learning. Never stop trying to learn. Never stop double-checking. I have to refer to my two grammar sites and other references. If you’re a designer, never stop researching. Dig into those data sheets. Read up on best practices. If you’re working a job over multiple sites, always make sure everyone’s using the same rules.

Over the next few days, I’m going to go back through my past posts and see how many of these “than/then” errors I can find and rework. Ugh.

Duane Benson
Never give up. Never surrender.

http://blog.screamingcircuits.com

Yeah, yeah. Top 10 predictions for the new year really need to be out in either the last week of the prior year or the first week of the new year. But I’m late. It’s because my oatmeal is lumpy and I’ve just been trying to decide if I should have a top predictions for the new year or for the decade. Some people would say that we’re still in the old decade, because, you know, 1 – 10. But I say, it’s only analog jockeys that say that. Digital drivers go from 0 – 9 (or 0 – 1 or 0 – F or 0 – 7… now I’m confused again. Not many go 0 – 7 these days). For the purposes of this document, I’m claiming to be more digital than analog, so the new millennia started in 2000 and this new decade starts now. Or, does that mean that the new millenia should start in 2048? Or, rather 0x800? Crud. That’s not a thousand. Okay, I don’t want to wait until 4096. I might be dead by then. Fine. It’s the year 3732. I have my handy 74LS90 and I’m going to count out my top 10 predictions.

Starting at count 0, with Qa = L, Qb = L, Qc = L and Qd = L:

0000: By the end of the decade, 50% of all passives will be embedded passives and 20% of all PCBs will have 90% or more of their passives embedded.

0001: By the end of the decade, Quad stack POP (package on package) will be commonplace.

0010: By the end of the decade, Each individual human will have their own IP address. Several of us will have more than one. That way, we can jury rig accelerometers into our hands and feet so we can wirelessly know where each of our extremities are at all times. Cats will have them too.

0011: By the end of the decade, solder paste will be used less often than not when assembling components on to PCBs.

0100: By the end of the decade, nearly all hydraulics and pneumatics in new motor vehicles will have been replaced by electrics.

0101: By the end of the decade,the first semi-autonomous passenger vehicle will be on display on the auto-show circuit. Hobbyist built semi-autonomous cars will already be on the road.

0110: By the end of the decade, “airline pilot” will generally be a really, really, really boring job. That’s a bit of a problem.

0111: By the end of the decade, most military “foot action” will consist of two soldiers in command of a squad of robots and those two soldiers will as likely be in Fort Lewis, Washington as in the combat zone.

1000: By the end of the decade, the president of the US will be promising health care reform as the highest priority.

1001: By the end of the decade, routine bioengineering will be, well, routine. Very scary.

1010: By the end of the decade, the 2019 recession will be looming large and all of the people that have forgotten about the 2009 recession and the 2001 recession and the 1985 recession and the 1975 recession… will be freaking out again.

1011: By the end of the decade, lead will be gone from 98% of new electronics. Bummer.

1100: By the end of the decade, four of the substances that replaced the substances removed from electronics due to ROHS and similar regulations will have been found to be significantly more harmful to the environment and the people recycling the materials than are the substances that they replaced.

1101: By the end of the decade, the world of intellectual property will be in even more of a mess than it is today. Virtually everything will be accessibly for easy theft and cheap replication. (This is pretty much a big “duh.”)

1110: By the end of the decade,building your own mutli-purpose robot will be as easy as building your own PC was in 1988. Hardware components and operating systems will be off the shelf, but standards will be pretty loosely defined, interoperability will be more theory than reality and applications will be sketchy and buggy.

1111: By the end of the decade, still no flying cars and personal jet packs, dadgummit!

Duane Benson
Sorry. I didn’t have a 74LS90. I only had a 74LS93

http://blog.screamingcircuits.com/