How do you design these days?
in [Design]
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From: Joerg on 1 Jan 2010 19:56 Michael A. Terrell wrote: > Jim Thompson wrote: >> On Fri, 01 Jan 2010 16:17:30 -0500, Phil Hobbs >> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >> >>> On 1/1/2010 3:56 PM, Joerg wrote: >>>> krw wrote: >>>>> Why are pin numbers an issue? You never probe from the backside of a >>>>> board? The spatial transform is pretty ingrained in me and I spent a >>>>> decade doing processor design (no PCB stuff). >>>> >>>> Until one fine day you have one of those Supertex high voltage chips. >>>> Some weirdness happens on the prototype boards, must be a software >>>> issue. It's always software. Has to be. Hmm, let's see how that looks on >>>> the old breadboard. Grab probe, lemmee see, serial data out was, uhm, >>>> umpteenth pin from upper left ... POP ... *PHOOMP* >>>> >>> How dull your life would be without fireworks, though. ;) >>> >>> Cheers >>> >>> Phil Hobbs >> Indeed! I haven't had a "fireworks" event since ~1980. > > > I wonder if Joerg demands at least one fire extinguisher in all his > design contracts? :) > There is one right here :-) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: krw on 1 Jan 2010 20:15 On Fri, 01 Jan 2010 12:56:24 -0800, Joerg <invalid(a)invalid.invalid> wrote: >krw wrote: >> On Thu, 31 Dec 2009 22:55:22 -0800 (PST), "miso(a)sushi.com" >> <miso(a)sushi.com> wrote: >> <snip> >>> The backwards pinout is an issue. I sharpie the pin numbers after I >>> mount the dead bug. >> >> Why are pin numbers an issue? You never probe from the backside of a >> board? The spatial transform is pretty ingrained in me and I spent a >> decade doing processor design (no PCB stuff). > > >Until one fine day you have one of those Supertex high voltage chips. >Some weirdness happens on the prototype boards, must be a software >issue. It's always software. Has to be. Hmm, let's see how that looks on >the old breadboard. Grab probe, lemmee see, serial data out was, uhm, >umpteenth pin from upper left ... POP ... *PHOOMP* Sparks wake one up. "Hmm, maybe it's not a software issue." A little smoke never hurt anyone and the feedback teaches one how to count.
From: krw on 1 Jan 2010 20:18 On Fri, 01 Jan 2010 18:12:35 -0500, "Michael A. Terrell" <mike.terrell(a)earthlink.net> wrote: > >Jim Thompson wrote: >> >> On Fri, 01 Jan 2010 16:17:30 -0500, Phil Hobbs >> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >> >> >On 1/1/2010 3:56 PM, Joerg wrote: >> >> krw wrote: >> > >> >>> Why are pin numbers an issue? You never probe from the backside of a >> >>> board? The spatial transform is pretty ingrained in me and I spent a >> >>> decade doing processor design (no PCB stuff). >> >> >> >> >> >> Until one fine day you have one of those Supertex high voltage chips. >> >> Some weirdness happens on the prototype boards, must be a software >> >> issue. It's always software. Has to be. Hmm, let's see how that looks on >> >> the old breadboard. Grab probe, lemmee see, serial data out was, uhm, >> >> umpteenth pin from upper left ... POP ... *PHOOMP* >> >> >> > >> >How dull your life would be without fireworks, though. ;) >> > >> >Cheers >> > >> >Phil Hobbs >> >> Indeed! I haven't had a "fireworks" event since ~1980. > > > I wonder if Joerg demands at least one fire extinguisher in all his >design contracts? :) Yeah, but he returns it, fully tested.
From: krw on 1 Jan 2010 20:19 On Fri, 01 Jan 2010 17:40:54 -0500, ehsjr <ehsjr(a)nospamverizon.net> wrote: >John Larkin wrote: >> On Thu, 31 Dec 2009 11:49:37 -0800, Joerg <invalid(a)invalid.invalid> >> wrote: >> >> >>>John Larkin wrote: >>> >>>>On Wed, 30 Dec 2009 20:02:02 -0800, D from BC >>>><myrealaddress(a)comic.com> wrote: >>>> >>>> >>>>>On Wed, 30 Dec 2009 20:01:39 -0600, "RogerN" <regor(a)midwest.net> >>>>>wrote: >>>>> >>>>> >>>>>>When I was in school components fit on solderless breadboards and we made >>>>>>circuits using breadboards, power supplies, meters and oscilloscopes. Many >>>>>>of today's components don't appear to be breadboard friendly, so how is it >>>>>>done today? >>>>>> >>>>>>Is circuit design software and simulation good enough to go straight to a PC >>>>>>board? Or do you use surface mount to breadboard adapters? Do you still >>>>>>use a soldering Iron to solder or paste solder and an oven? >>>>>> >>>>>>I'm wanting to tinker with some circuits but some chips I'm interested in >>>>>>only comes in MSOP or other packages that look intimidating to attempt to >>>>>>solder. >>>>>> >>>>>>Thanks! >>>>>> >>>>>>RogerN >>>>>> >>>>> >>>>>My motto: >>>>>If it works on a breadboard, it's not worth producing. >>>>> >>>>>On my current project, I have to feed the simulator pcb parasitics and >>>>>component parasistics to get accurate simulations. >>>>>I've had to bench test to get some parasitics. Once parasitics are >>>>>included, scope results and simulation results get close. >>>>> >>>>>If all looks good on sim, I make a pcb, etch it and bench test it. >>>> >>>>One problem is that device models often aren't available for fast >>>>parts, or all you get are S-params when you need large-signal >>>>time-domain stuff. So sometimes you can learn a lot by hacking some >>>>FR4 and testing parts. >>>> >>>>I never breadboard entire products, or even complex circuits... just >>>>enough to characterize parts or simple subcircuits. >>>> >>>>This is an EL07 driving a PHEMT... >>>> >>>>ftp://jjlarkin.lmi.net/BB_fast.JPG >>>> >>>>which made decent 5-volt, 1 GHz square waves. >>>> >>> >>>How do you get those nice clean cuts into the copper? >> >> >> Just x-acto. The magic trick is to then rub it hard with a Scotchbrite >> pad. That removes the burrs. >> >> John >> > >You've got a steadier hand than I'll ever have. >I have to do it with a Dremel mounted in a drill press >adapter, and slide the board against guides clamped to >the bed. Even then ... :-( Sounds like you need a small milling machine.
From: krw on 1 Jan 2010 20:23
On Fri, 01 Jan 2010 16:43:18 -0500, Spehro Pefhany <speffSNIP(a)interlogDOTyou.knowwhat> wrote: >On Fri, 01 Jan 2010 14:25:44 -0600, the renowned krw ><krw(a)att.bizzzzzzzzzzz> wrote: > > >> >>>http://speff.com/cream.jpg >> >>Great shot (I trust it's not recent). > >No, there's a good 0.25" of snow on the ground at the moment. Even >poor old Buffalo isn't buried for once (popped down last week to see >the Penguins game- bargain prices, relatively speaking). > >> I love Goldens. The light ones >>aren't common at all. Seems the breed has been taken over by the red >>ones. > >She's a gem- almost 9 y.o. now. Very good personality with kids. You >have to be careful to get a reputable breeder- Goldens have a tendency >to severe hip problems that can hit later in life. No puppy mills. Our Golden was great with kids too. My son could just about maul him and he'd just sit there and take it. >Kitten mills, OTOH: >http://smg.photobucket.com/albums/v108/earlbrown/buickstuff/enginebuild/?action=view¤t=IM002539.jpg > ROTFLOL. Our cats have all been really friendly. The two we have now always lay on us when we're watching the tube. |