Surface Mount Devices Field Repair

[Kmagrill]

The recent topic discussing the high degree of integration and SMD technology in a manufacturer's transmitter leads me to wonder what the future of our industry is, given the negative comments when SMD technology is employed. How will we manufacturers will be able to produce equipment in the future without the use of SMD?

Very little new technology is being released in through-hole designs and older parts are now getting harder to find. Those that are available in thru-hole are frequently 2x the cost of the same SMD part. The industry moves towards ever more sophisticated designs, yet those designs have reached the stage where building them is impossible, or impractical at a reasonable cost, using old technology.

We, as well as many other manufacturers, continue to design as much as possible using through hole technology, but we really have no choice for the high tech stuff. Often, our designs are a combination of the two.

Having worked with SMD stuff, it's certainly harder to field repair than popping a chip out of a socket, but compared to desoldering a through-hole chip from a board, it's about the same. Yes, there are special techniques that should be employed, but I've found that it's quite possible to do emergency repairs with nothing more than a soldering iron (two is better, though). In fact, with a little practice, it's not hard to do at all with no special tools. Now, I would have answered differently 5 years ago, before we started working with it. Back then, I would have said you need special tools and a big magnifying glass or loupe. For manufacturing rework, proper tools do help, but they are not essential for occasional repair. I also noticed that the cost of SMD tools has gotten pretty reasonable. For less than $100 you can buy some pretty nice SMD stuff, directly from China (yes, it works very well), on eBay.

Don't get me wrong, I'm no big fan of SMD. I wish stuff was all available in through-hole, but the reality is that we are near the end of that phase of technology, so we are adapting in order to stay current.

So, what do you all think of the trend towards SMD technology?

Will you adapt to it, or will you try to buy around it for as long as possible?

 

[Studio1]

You've basically said it all and I agree with what you have put forward.

Modern electronics has benefited greatly from SMD technology, and allowed units to remain relatively small. Undoubtedly some equipment that fits in a 1U case would require something double that size if it was all made with through-hole componentry.

I did mention something along these lines a while back in the thread on 8100A Optimods.
These things (as an example) are easily repaired in the field, with all components (which are likely to die) being through-hole and easily obtained from most electronics suppliers.

Any self-respecting manufacturer of professional equipment should provide sockets for DIL ICs. I would not expect to open a piece of broadcast gear and see ICs soldered directly to the board!
Obviously, sockets don't work for SMD stuff - so they have to be direct soldered.

Chances are, they're a proprietary part as well - custom made for the application. While you are likely to have a handful of TL072 op-amps in your repair kit or your parts cupboard, it's highly unlikely you'll have a ASX77889-AH445 tucked away for the possible scenario of it releasing the smoke at 3am on a stormy night.

Not only that, but it will be a digital processing chip of some sort, and you'll need some pretty fancy electronic test gear to determine whether it's at fault, or whether the problem lies elsewhere in the unit.

Few stations can afford to invest tens of thousands of dollars in specialist diagnostic and repair equipment on the off-chance that a unit might go toes-up at some stage and need repair. There is also the service information required in order to perform such surgery, and this may not be available from the manufacturer.

This means that any units using proprietary parts or specialised SMD must be covered by back-up equipment, while they are sent back to the manufacturer for repair or replacement.
Either that, or it's necessary to keep stocks of replacement boards on hand for every device you own.

A lot of industries now rely on 'board-changing'. SMD and multi-layer boards are wide-spread in electronic equipment and field-servicing down to component level is virtually impossible, if not impractical.

Yes, modern equipment is reasonably reliable, but it does break down - and usually at the worst possible moment.

 

[greg.hahn]

So, what do you all think of the trend towards SMD technology?

Will you adapt to it, or will you try to buy around it for as long as possible?

The only logical answer is to adapt to it. The electronics world is changing, and we have to roll with the punches and adapt our methods. That might mean having a backup transmitter is more important now than it used to be.

But it's crazy to buy a new product in 2012 full of 1982 technology.

 

[Studio1]

But it's crazy to buy a new product in 2012 full of 1982 technology.

Agreed, and it would be mad to have to work on modern units that were full of boards covered in TTL ICs and so on.

 

[w9wi]

To be honest, how often do we do component-level repair anyway?

At least in TV, I've gone weeks (if not months) without lifting a soldering iron -- when I do, it's usually to repair a cable... Transmitter work usually involves module swaps; anything in the studio is usually either a software repair or a board swap. The test gear necessary to troubleshoot problems in modern gear to the component level is not really practical to own.

I'm sure the situation is somewhat different in radio -- for one thing, you guys haven't seen all your transmitters obsoleted through regulation -- but the nature of your studio work has certainly changed dramatically.

Point being, that for reasons that worked parallel to the SMD conversion but weren't necessarily tied to it, the SMD conversion isn't really as big of a problem as it might have been.


What I think may be a bigger concern... is the effect on hobby electronics. (which is where our next generation is going to come from) Homebrewing with this stuff is going to be a problem. (though maybe not as big of a problem as the growing difficulty in obtaining parts of any package in small quantities) We do have Sparkfun offering "breakout boards", where they'll mount a SMD chip on a board & bring out the leads to pads that are actually visible...

 

[speakerman]

I started off with flame bottles years ago and had to evolve or become extinct. I got this at Frys last year and did a lot of practice on dead boards to learn the techniques. I already fixed a number of items including an iMac that needed the graphics chip re-flowed to reconnect the ball-grid connections. You need a magnifier lamp on the bench to do the really fine work with small components.

There are some Youtube videos to help out the learning process.

You can spend more money however this seems to do the job for me.

http://www.aoyue.com/en/ArticleShow.asp?ArticleID=379