How do you design these days?
in [Design]
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From: Joerg on 31 Dec 2009 18:51 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. > Wow, that is a precise X-acto cut. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Falk Willberg on 31 Dec 2009 18:52 Jan Panteltje schrieb: > On a sunny day (Thu, 31 Dec 2009 14:54:10 -0800) it happened Joerg > <invalid(a)invalid.invalid> wrote in <7q4ocpFid2U2(a)mid.individual.net>: >>> Real man use no PeeSeeBee: >>> ftp://panteltje.com/pub/z80/graphics_card_top.jpg Why did I know that I would see an 6845 when it completely loaded? >>> ftp://panteltje.com/pub/z80/graphics_card_bottom.jpg >>> :-) >>> >> <GASP> >> >> I think I am going to get sick ... > > Have to point out that that worked without a single problem for > 10 years. That's the annoying thing with this kind of "implementation": It often just works. > And it will likely still work if the EPROM has not lost data. > But it has been superseded by better tech. > You are not afraid of soldering some wires no? My first CP/M computer was made the same way, but I used enameled copper wire[0] on the solder side only. My brother wrote his first 100+ job applications on this beast (Wordstar + DBase). Falk [0]I still use it: http://falk-willberg.de/LiPo-Lader-web.JPG (the 5 "thick" wires)
From: Joerg on 31 Dec 2009 18:52 Jan Panteltje wrote: > On a sunny day (Thu, 31 Dec 2009 14:54:10 -0800) it happened Joerg > <invalid(a)invalid.invalid> wrote in <7q4ocpFid2U2(a)mid.individual.net>: >>> Real man use no PeeSeeBee: >>> ftp://panteltje.com/pub/z80/graphics_card_top.jpg >>> ftp://panteltje.com/pub/z80/graphics_card_bottom.jpg >>> :-) >>> >> <GASP> >> >> I think I am going to get sick ... > > Have to point out that that worked without a single problem for > 10 years. > And it will likely still work if the EPROM has not lost data. > But it has been superseded by better tech. > You are not afraid of soldering some wires no? Not at all, but I use thin copper-enameled wires and run them in orderly fashion :-) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: MooseFET on 31 Dec 2009 18:58 On Dec 31, 1:55 pm, n...(a)puntnl.niks (Nico Coesel) wrote: > Raveninghorde <raveninghorde(a)invalid> wrote: > >On Thu, 31 Dec 2009 06:25:56 -0800 (PST), MooseFET > ><kensm...(a)rahul.net> wrote: > > >>On Dec 30, 6:01 pm, "RogerN" <re...(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. > > >>I use ExpressPCB to make boards for parts of the design. Things like > >>power supplies are made as a PCB with connectors that are wired to the > >>other boards. I use 1206 parts and put in some extra parts and layout > >>such that cuts and jumps are easy(ish) to do. > > >>> Thanks! > > >>> RogerN > > >Think. Read data sheets. Think. CAD. Make on production line. > > >Pcb design rarely takes longer than a lash up on strip board or > >whatever and always works better. > > >Very occasionally I have lashed up a small part of a design but I > >almost always regret the waste of time. > > The truth lies somewhere in between. I use whatever seems most handy > given the situation. For analog I use simulation a lot but it always > gets prototyped. SMD components either end up as a dead bug on > prototyping board or a small dedicated PCB. RF and power means having > a small PCB made. Sometimes I like to try things like a new > microcontroller. I usually make universal (=a load of via's to connect > wires to) boards out of such a project so they can serve as a > kickstart for prototyping other projects. It is very hard to hook a spice model to the real transducers. Making a spice model of the transducer isn't so easy when it is pushing the limits of physics and you have to assume that the physics guy got it exactly right when he did his equations. Very few op-amps have truly accurate spice models. They don't cover things like the recovery from hitting the rails or slew rate limits. They almost all beam electrons in from some other universe. Models of inductors are not super accurate. Even the ones that cover saturation are only approximations. If you have to write software to go with the hardware, it is very nice to debug on something like the real hardware. > > -- > Failure does not prove something is impossible, failure simply > indicates you are not using the right tools... > nico(a)nctdevpuntnl (punt=.) > --------------------------------------------------------------
From: Jan Panteltje on 31 Dec 2009 19:08
On a sunny day (Thu, 31 Dec 2009 15:52:38 -0800) it happened Joerg <invalid(a)invalid.invalid> wrote in <7q4rqdF317U2(a)mid.individual.net>: >Jan Panteltje wrote: >> On a sunny day (Thu, 31 Dec 2009 14:54:10 -0800) it happened Joerg >> <invalid(a)invalid.invalid> wrote in <7q4ocpFid2U2(a)mid.individual.net>: >>>> Real man use no PeeSeeBee: >>>> ftp://panteltje.com/pub/z80/graphics_card_top.jpg >>>> ftp://panteltje.com/pub/z80/graphics_card_bottom.jpg >>>> :-) >>>> >>> <GASP> >>> >>> I think I am going to get sick ... >> >> Have to point out that that worked without a single problem for > 10 years. >> And it will likely still work if the EPROM has not lost data. >> But it has been superseded by better tech. >> You are not afraid of soldering some wires no? > > >Not at all, but I use thin copper-enameled wires and run them in orderly >fashion :-) Bu the vapour of the enamel is poisenous :-). I tried that stuff, it stinks. Normally I use flat cable: ftp://panteltje.com/pub/z80/sound_card_bottom.jpg ftp://panteltje.com/pub/z80/soundcard_top.jpg That flat vertical thing is a R2R network, the DAC. Top right an electret mike, Bottom right a DC-DC converter for the negative voltage of the TIL084s Audio amp: LM380, ADC: ADC804 SAA1099 for sound effects... (did not really use that, used wave tables). the resistors and caps in the IC sockets are part of the anti-aliasing filters. Also wrote a sound editor for it, all 8 bits of course. |