I can't remember the last time where six digital parts would have cost $12 in any of my designs. More like 10c times six :-)
[...]
Yep, that gets expensive. Maybe you are better off in Alabama than we are in California.
We sometimes calculate them in millicents :-)
Maybe someone should have a chat with the analog guys ;-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Some noble names among the ones I've seen. Now there are even places specializing in BGA failure repair:
Quote "We fix 80% of BGA failures, ..."
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Small ones can be ok but large BGA cannot easily stand the flexing of a circuit board. All it takes is one fall. BGA don't have any compliance to speak of while the leads of TSSOP and others can bend a little without popping out of the solder.
That is amazing. To be honest, I wouldn't attempt this job. I'd send the board away to a pro-shop.
The top ones should hold well but the problem is the circuit board.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
No wonder you don't think digital stuff is fun. You're too cheap to buy interesting parts. Other than passives and transistors, there is not much we buy that costs less than a buck.
It's sometimes necessary. Our main business is so cyclical that we need the control in-house manufacturing gives. Certainly control over production trumps cost.
In more ways than one. ;-)
Our product markups are better than what Larkin claims (and our quantities higher), so millicents aren't the main issue. I just started a cost reduction design pass on our products but I'm certainly not looking at millicents. Our fixed costs drown that out. Molds are
*expensive*.Start with TI's. ;-) I'd even add a couple more to get rid of the single-ended analog. We also have isolation requirements so some supplies show up on both sides of the barrier. They are paranoid about running the analogs and digital stuff from the same supplies (and grounds!) too. ...even though neither are being taxed.
[...]
I do occasionally get involved with uC but it's not much fun for me. Usually I leave that to teh experts, just like DSP.
The you may be leaving money on the table :-)
Yeah, maybe some day we'll join you.
In the end it boils down to whether the lower cost is or was worth the NRE.
Don't use the fancy parts :-)
I am usually pretty brazen in that respect. Single-supply analog as much as possible, I normally don't object sharing the supplies with the digital guys as long as they share their Christmas cookies, and iso supplies are home made using little transformers and some sort of bridge driver (as long as not over a buck ...).
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
UCs are all the same anymore. We have another group of engineers to screw them up. ;-)
My time is worth money too, as is another board spin.
It's a pretty place (no mountains or snow, though) but rather quiet. This is a fairly big "small town". If I moved it would likely be
100NE to Atlanta. Atlanta is a *really* big small town. ;-)Yep. There were some decisions made that are going to be hard to counter. The real savings (like 2x $15 for pots) are going to break the mold.
Don't use TI.
I don't like throwing away the "free" PSRR. I'm planning on combining supplies to save space more than the cost of the components. Interboard connectors are expensive and a PITA. The isos we're using are bricks (=expensive).
I think this depends on the application. A one mm thick mobile phone size FR4 board should not flex very much and maybe for bigger boards you could use more screws, but you might be right for the baking tray size boards you do, used in Ariane rockets and similar things :-)
-- Frank Buss, fb@frank-buss.de http://www.frank-buss.de, http://www.it4-systems.de
[...]
I remember a Burr-Brown sales rep trying to wet my appetite for an iso amp in the late 80's. I was interested a little, until he told me what it cost. 80 (!) bux. I can't remember ever having used iso power converter bricks or iso amp bricks/chips. Not even on expensive gear where it would have mattered less. Besides cost you'll typically be married to one single source and when that manufacturer can't deliver things turn ugly real fast.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
For commercial aircraft it often has to be rated for 20G, rated meaning it must not fail at all. On spacecraft it's several times that rating. A target lifetime of 30 years is also quite normal. But even regular small size boards are vulnerable. I don't remember the product but it was an expensive computer play station for kids that had a noticeable BGA failure rate (XBox?). Not sure if that's fixed by now.
BTW, since changing news servers I am having trouble with the German NG. Often it disappears and all threads must be re-loaded. Other times like this morning it doesn't download any new posts. It's only that NG, all the others always work. Sometimes it comes back after an hour. Very strange.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
You should contact your usenet provider, sounds like they have some peering problems. But I don't see any new posting in de.sci.electronics since today
1:33 am GMT either, maybe it is a sleepy sunday :-)-- Frank Buss, fb@frank-buss.de http://www.frank-buss.de, http://www.it4-systems.de
Oh, then it's probably not a server problem. My usenet provider is now the university server in Berlin, after our phone company cut all newsgroups.
I hope that group doesn't follow others and become a dinosaur ;-)
Do you think that having to reload all threads could also be a peering problem? Sometimes in the morning all NGs load with new posts except d.s.e. Then when I click on d.s.e. it asks as if I had just newly subscribed, "Download all 56782 headers?". Of course then I only download 1000 or so, otherwise this takes forever. Sometimes all of them will be marked as un-read, sometimes not. I can't imagine this being a Thunderbird problem because it never happens to any other NG.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
There is a chip for that ;)
--
Boris Mohar
On a sunny day (Sun, 30 Aug 2009 06:18:29 -0700) it happened Joerg wrote in :
News articles are indexed by number. If the server maintainer edits the list, and changes numbering to start with a lower number, then you have this effect. He should not do that. Change servers. Try
If it persists I'll first write to them. It's news.individual.net and they are very responsive.
Well, I just changed :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
The bricks go for about a buck-a-watt. The bricks we're using are standardized (we've switched a few times already). The real problem with any of this is compliance. It costs a lot of money to change a switcher.
The thing that appalled me was what we're paying for isolated RS-422 transceivers! We're using them for essentially DC, too. It'll be at least another month before I get to that part of the system.
EMC can be nasty. I have seen bricks fail at the lab while their manufacturers were staunchly saying that they'd pass with flying colors. Thing is, my time is expensive, as is yours. But spending 8h on a switcher design is better than pulling your hair out after a day at the EMC lab and having to call the boss asking him to tell the marketeers that we won't make the trade show this time.
But be careful if they connect system parts at different locations. I've seen a guy ask his colleague "Hey, why does this little data cable get hot? How is that possible?"
Lightning and spikes are another concern.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
We had a wall wart, that was already certified, fail in compliance testing. Turns out that the manufacturers only test with a resistive load at full ratings.
EMC testing for a trade show? ;-)
Sure, but there are cheaper ways of isolating "DC" signals.
We're thinking about going to fiber for just this reason. The problem is that it forces the customer to supply power. ...and we already pulled the remote power option from the remote transceiver (see wall wart issue above).
That does not surprise me. One reason why I like to roll my own.
Yes. At medical trade shows you must often be able to deliver next day, right to the show location. In Europe it is customary that interested hospitals send people with trucks, to land and execute a deal right then and there. Others want it delivered to their hospital next week Monday when they are back. IOW you better have a substantial amount of merchandise on the shelf, ready to ship the millisecond a sales guy calls in a deal.
Imagine you find "the" digital scope at a show. Drooling all over the place. You'd probably walk away from it if the vendors says "Well, we have a three month leadtime on this one".
Yes, for DC all need is a 20c optocoupler.
Or go with a transformer wall wart.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
The safety certifications are easier with a purchased solution, though.
By the time we have a saleable system there is no need for trade shows. Different industry norms, I guess.
Three months isn't an issue. It would take that long to convince myself that I really wanted that model (and get the cash loose to buy it). ;-)
Exactly where I was going. Since there is already an isolated supply for this interface and opto-isolator is pretty cheap.
I suggested that last week for a different application. I got funny looks but no reasons it couldn't be done.
[...]
If they come from a manufacturer you can trust. The worst I've seen: Fully "certified" open frame supply from one of the traditional PS manufacturers. Submitted unit to the TUEV, they did the usual overload tests ... *PHUT*. Could have been a fluke so they tested a 2nd system ... *PHUT*.
I read the folks at that vendor the riot act and had purchasing cancel the whole order. Their sales guy was almost in tears.
Ok, for personal use, yes. Hospitals and much of the industry must time their purchases into a tax year. Government-run places must often blow out the remainder of the budget by this and this date or they'll have next year's budget cut by that amount. That's sick, but this is unfortunately how it is.
[...]
Pull out the bill for the last failed EMC test, along with a good faith estimate of company engineering hours put into it, travel expenses, the works. That ought to convince them :-)
Of course if your gear must ship internationally you don't have much of a choice, then you nowadays need a 90-260VAC universal supply.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.