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From: Joerg on 21 Apr 2008 09:49 krw wrote: > In article <6PQOj.21063$%41.8783(a)nlpi064.nbdc.sbc.com>, > notthisjoergsch(a)removethispacbell.net says... >> John Larkin wrote: >>> On Sun, 20 Apr 2008 14:13:21 -0700, Joerg >>> <notthisjoergsch(a)removethispacbell.net> wrote: >>> >>>> John Larkin wrote: >>>>> On Sat, 19 Apr 2008 14:17:44 -0700, Joerg >>>>> <notthisjoergsch(a)removethispacbell.net> wrote: >>>>> >>>>>> Nico Coesel wrote: >>>>>>> Dave <dhschetz(a)gmail.com> wrote: >>>>>>> >>>>>>>> Does anybody out there have a good methodology for determining your >>>>>>>> optimal FPGA pinouts, for making PCB layouts nice, pretty, and clean? >>>>>>>> The brute force method is fairly maddening. I'd be curious to hear if >>>>>>>> anybody has any 'tricks of the trade' here. >>>>>>> I start thinking about how the PCB should be routed the minute I start >>>>>>> to draw a schematic. I always draw components with their actual >>>>>>> pin-outs. This helps to group pins together and it helps to >>>>>>> troubleshoot the circuit when the prototype is on your bench (no need >>>>>>> to lookup the pinouts because they are in your diagram). >>>>>>> >>>>>> For quad opamps like the LM324 as well? That can make a schematic harder >>>>>> to read and will also cause a nightmare if the layouter wants to swap >>>>>> amp A with amp C and stuff like that. >>>>>> >>>>>> [...] >>>>> A quad opamp doesn't have 1738 pins! >>>>> >>>> Well, yes, I was just wondering about whether Nico really always draws >>>> the physical package. Looks like he doesn't for smaller stuff. >>>> >>>> With 1738 pins you can only hope that the FPGA has enough routing >>>> resources. That used to be a major pain in the early 90's. Don't know >>>> about nowadays since other guys design the parts with the big FPGAs. And >>>> I am glad I don't have to deal with BGA, at least not with large ones ... >>> The biggest ones we use are Sparten 3's with 456 balls on 1 mm >>> centers. We haven't had any routing problems so far, doing pretty >>> complex stuff at 128 MHz clock rates. Our in-house BGA soldering >>> yield, to date, is exactly 100%. BGAs seem to be a lot easier to >>> solder reliably than fine-pitch leaded parts. Easier to inspect, too, >>> since you can't inspect them at all. >>> >> The latter is a concern in my field (medical). We need to be able to >> inspect. The other concern is involuntary board flexing. Most of my >> designs have to sustain under tortures such as freighter pilots >> ploughing through a storm in the Carribean in airplanes as old as a DC-3 >> or a trucker in Africa who is lead-footing it over a few hundred miles >> of washboard road. >> > X-Rays? > They tend not to penetrate through metal so well and are frowned upon at the work place. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joel Koltner on 21 Apr 2008 12:56 Hi Joerg, "Joerg" <notthisjoergsch(a)removethispacbell.net> wrote in message news:PLsOj.7522$GE1.332(a)nlpi061.nbdc.sbc.com... > Private companies generally offer zilch in retirement benefits. Those days > are long gone. Actually I think a very significant fraction of companies (at least those hiring EEs) offer some sort of contribution to 401k plans, sometimes profit sharing, sometimes stock options, etc... but I concur that the old days of "company pensions" is pretty much gone. > A 70 year old programmer can be better than a 40 year old. Absolutely, but if you're an employer it's definitely a legitimate consideration that starting a bunch of 70-year-olds on a, say, decade-long "modernization" project is rather riskier than if you toss a few 50- or 30-year-olds into the mix as well. :-) > Anyhow, why should retirement checks be based on the last year of service? > IMHO that's wrong. I agree that one year seems too short, but trying to figure out how many years should be taken into consideration (which is effectively what happens in private companies if the company is contributing to your 401k) is not going to be easy either. ---Joel
From: Joel Koltner on 21 Apr 2008 13:04 "John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message news:coen041brmqf342022figkpv9ogjol2h0i(a)4ax.com... > Easier to inspect, too, > since you can't inspect them at all. I'm sure you know this, but plenty of places will X-ray BGAs to "inspect" them.
From: Joerg on 21 Apr 2008 14:56 Joel Koltner wrote: > Hi Joerg, > > "Joerg" <notthisjoergsch(a)removethispacbell.net> wrote in message > news:PLsOj.7522$GE1.332(a)nlpi061.nbdc.sbc.com... >> Private companies generally offer zilch in retirement benefits. Those days >> are long gone. > > Actually I think a very significant fraction of companies (at least those > hiring EEs) offer some sort of contribution to 401k plans, sometimes profit > sharing, sometimes stock options, etc... but I concur that the old days of > "company pensions" is pretty much gone. > Mostly it's a mere pittance. And that's ok, I am a strong believer that everyone should pull their own weight. Except disabled people, of course. >> A 70 year old programmer can be better than a 40 year old. > > Absolutely, but if you're an employer it's definitely a legitimate > consideration that starting a bunch of 70-year-olds on a, say, decade-long > "modernization" project is rather riskier than if you toss a few 50- or > 30-year-olds into the mix as well. :-) > True. However, we should embrace the Japanese concept of letting older folks teach the young ones, not lay them off. >> Anyhow, why should retirement checks be based on the last year of service? >> IMHO that's wrong. > > I agree that one year seems too short, but trying to figure out how many years > should be taken into consideration (which is effectively what happens in > private companies if the company is contributing to your 401k) is not going to > be easy either. > Just make it the same as with 401(k), IRA, old style pension funds, social security etc. What counts is what you pay in over your whole career. We can read such stories almost daily, just an example from this morning: http://www.sacbee.com/111/story/876845.html Guess who gets to pay the tab for the agency's legal defense? -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joel Koltner on 21 Apr 2008 15:40
"Joerg" <notthisjoergsch(a)removethispacbell.net> wrote in message news:Jr5Pj.4650$vF.1890(a)newssvr21.news.prodigy.net... > Mostly it's a mere pittance. And that's ok, I am a strong believer that > everyone should pull their own weight. I guess it depends on the employer... Do you see anything bad about the old system of pensions (from private companies, ignore the government for the moment)? I see them more as "different" than particularly better or worse. These days you're personally responsible for more of your retirement planning, which has the upside that you can probably do a better job than some company-wide pension programs used to do, but the downside is that those who plan poorly (or not at all) end up needing that much more government assistance once they're retired. > True. However, we should embrace the Japanese concept of letting older folks > teach the young ones, not lay them off. Yes, agreed 100%. > Just make it the same as with 401(k), IRA, old style pension funds, social > security etc. What counts is what you pay in over your whole career. The end result there is that if your employer requires you to move to, e.g., California for the last few years of employment you'll pretty much be forced to then immediately move when you hit retirement. I suppose that isn't particularly awful, since that fact would have been clear when the employer said, "move!" > Guess who gets to pay the tab for the agency's legal defense? Sheesh... screw the taxpyers with retiremend funding and then screw'em again when someone tries to blow the whistle. Nice... ---Joel |