Through Hole vs. Surface Mount
in [Design]
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From: Joerg on 1 Apr 2010 13:49 krw(a)att.bizzzzzzzzzzzz wrote: > On Wed, 31 Mar 2010 16:52:24 -0700, Joerg <invalid(a)invalid.invalid> wrote: > >> krw(a)att.bizzzzzzzzzzzz wrote: >>> On Wed, 31 Mar 2010 13:30:12 -0700, Joerg <invalid(a)invalid.invalid> wrote: >>> >>>> Robert Baer wrote: >>>>> Archimedes' Lever wrote: >>>>>> On Tue, 30 Mar 2010 09:42:05 -0700, Joerg <invalid(a)invalid.invalid> >>>>>> wrote: >>>>>> >>>>>>> All I can tell you is that there is no glop. I just did a few more >>>>>>> solder joints and held them under a magnifier -> nada, zilch, clean. >>>>>>> >>>>>>> Maybe you used the wrong temperature? My Weller is running at 640F >>>>>>> right now. >>>>>> Most 'no-clean' hand operations I ever saw left the perfectly formed >>>>>> solder joint encapsulated in a thin flux film. Are you sure that you are >>>>>> not just too old or too non-detail oriented to 'see' it, even though it >>>>>> is there? >>>>>> >>>>>> The flux does not evaporate, and is, by design, meant to remain, so it >>>>>> *has* to be there... literally. >>>>> Check! >>>>> That is the glop i was talking about. >>>> Then why doesn't anything corrode out here? Even stuff where there is >>>> extensive scratching by alligator clips never developed a problem. >>>> >>>> Now RoHS solder, that's a whole 'nother story. Don't get me started ... >>> We use RoHS solder and a no-clean flux. Hows that grab ya'. ;-) >> >> That gives me the goose bumps ;-) > > Europeons. What are you going to do? Try to get in on one of the exemptions :-) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 1 Apr 2010 13:50 JosephKK wrote: > On Wed, 31 Mar 2010 13:25:55 -0700, Joerg <invalid(a)invalid.invalid> wrote: > >> John Devereux wrote: >>> Joerg <invalid(a)invalid.invalid> writes: >>> >>>> Archimedes' Lever wrote: >>>>> On Tue, 30 Mar 2010 09:42:05 -0700, Joerg <invalid(a)invalid.invalid> >>>>> wrote: >>>>> >>>>>> All I can tell you is that there is no glop. I just did a few more >>>>>> solder joints and held them under a magnifier -> nada, zilch, >>>>>> clean. >>>>>> >>>>>> Maybe you used the wrong temperature? My Weller is running at 640F >>>>>> right now. >>>>> Most 'no-clean' hand operations I ever saw left the perfectly formed >>>>> solder joint encapsulated in a thin flux film. Are you sure that you are >>>>> not just too old or too non-detail oriented to 'see' it, even though it >>>>> is there? >>>>> >>>>> The flux does not evaporate, and is, by design, meant to remain, so it >>>>> *has* to be there... literally. >>>> Ok, but it hasn't corroded or otherwise tainted one lone solder joint >>>> in years. If it does cause a failure 300 years down the road I think I >>>> could live with that :-) >>> We use it for everything, never had a problem either. >>> >>> I take "no-clean" to mean "do not clean". I have heard (here) of >>> problems when cleaning is attempted, the insulating component is washed >>> away leaving an ionic residue which can absorb water and conduct. Or >>> something. >>> >> Even then I had no problems. Many times in my lab I lash up jigs, on >> Monday for example a tester to run transformers at 50Hz, 60Hz, 400Hz or >> wherever. That stuff gets a beating over time, alligator clips are >> attached to soldered areas over and over again so things become scraped. >> Never a problem. > > Try it for high impedance circuits >> 1E7 Ohms. I avoid that wherever possible. If needed it's best to work with guard rings. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 1 Apr 2010 21:59 Tim Williams wrote: > "Tim Williams" <tmoranwms(a)charter.net> wrote in message > news:hoot3i$n54$1(a)news.eternal-september.org... >> I've got a school project which, like most of my stuff, is through hole, >> but I cheaped out on gate drivers and went with complementary MOSFETs >> instead. They only come in SO-8, of course: >> http://myweb.msoe.edu/williamstm/Images/EE409_PWM1.jpg >> Way easier than laminating two sides that don't line up, then drilling >> cockeyed holes. > > And here's the stuff soldered down: > http://myweb.msoe.edu/williamstm/Images/EE409_PWM3.jpg > > Nope, no SMT caps. I'll stock up some day, but at the moment I can't > justify buying all the resistors and caps and diodes and transistors I'd > need to build complete SMT circuits. > If you ever do, get resistor and capacitor kits. Yeah, it'll be a few hundred bucks each but then you have over 100 parts of each value. I have clients who never buy resistors anymore for prototypes because these kits last and last. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: JosephKK on 2 Apr 2010 00:59 On Thu, 01 Apr 2010 10:50:50 -0700, Joerg <invalid(a)invalid.invalid> wrote: >JosephKK wrote: >> On Wed, 31 Mar 2010 13:25:55 -0700, Joerg <invalid(a)invalid.invalid> wrote: >> >>> John Devereux wrote: >>>> Joerg <invalid(a)invalid.invalid> writes: >>>> >>>>> Archimedes' Lever wrote: >>>>>> On Tue, 30 Mar 2010 09:42:05 -0700, Joerg <invalid(a)invalid.invalid> >>>>>> wrote: >>>>>> >>>>>>> All I can tell you is that there is no glop. I just did a few more >>>>>>> solder joints and held them under a magnifier -> nada, zilch, >>>>>>> clean. >>>>>>> >>>>>>> Maybe you used the wrong temperature? My Weller is running at 640F >>>>>>> right now. >>>>>> Most 'no-clean' hand operations I ever saw left the perfectly formed >>>>>> solder joint encapsulated in a thin flux film. Are you sure that you are >>>>>> not just too old or too non-detail oriented to 'see' it, even though it >>>>>> is there? >>>>>> >>>>>> The flux does not evaporate, and is, by design, meant to remain, so it >>>>>> *has* to be there... literally. >>>>> Ok, but it hasn't corroded or otherwise tainted one lone solder joint >>>>> in years. If it does cause a failure 300 years down the road I think I >>>>> could live with that :-) >>>> We use it for everything, never had a problem either. >>>> >>>> I take "no-clean" to mean "do not clean". I have heard (here) of >>>> problems when cleaning is attempted, the insulating component is washed >>>> away leaving an ionic residue which can absorb water and conduct. Or >>>> something. >>>> >>> Even then I had no problems. Many times in my lab I lash up jigs, on >>> Monday for example a tester to run transformers at 50Hz, 60Hz, 400Hz or >>> wherever. That stuff gets a beating over time, alligator clips are >>> attached to soldered areas over and over again so things become scraped. >>> Never a problem. >> >> Try it for high impedance circuits >> 1E7 Ohms. > > >I avoid that wherever possible. If needed it's best to work with guard >rings. So do i, still, i did enough stuff at 1E8 Ohms and some much higher (1E12 Ohms) to have a real respect for doing that routinely.
From: Joerg on 2 Apr 2010 11:01
JosephKK wrote: > On Thu, 01 Apr 2010 10:50:50 -0700, Joerg <invalid(a)invalid.invalid> wrote: > >> JosephKK wrote: >>> On Wed, 31 Mar 2010 13:25:55 -0700, Joerg <invalid(a)invalid.invalid> wrote: >>> >>>> John Devereux wrote: >>>>> Joerg <invalid(a)invalid.invalid> writes: >>>>> >>>>>> Archimedes' Lever wrote: >>>>>>> On Tue, 30 Mar 2010 09:42:05 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>> wrote: >>>>>>> >>>>>>>> All I can tell you is that there is no glop. I just did a few more >>>>>>>> solder joints and held them under a magnifier -> nada, zilch, >>>>>>>> clean. >>>>>>>> >>>>>>>> Maybe you used the wrong temperature? My Weller is running at 640F >>>>>>>> right now. >>>>>>> Most 'no-clean' hand operations I ever saw left the perfectly formed >>>>>>> solder joint encapsulated in a thin flux film. Are you sure that you are >>>>>>> not just too old or too non-detail oriented to 'see' it, even though it >>>>>>> is there? >>>>>>> >>>>>>> The flux does not evaporate, and is, by design, meant to remain, so it >>>>>>> *has* to be there... literally. >>>>>> Ok, but it hasn't corroded or otherwise tainted one lone solder joint >>>>>> in years. If it does cause a failure 300 years down the road I think I >>>>>> could live with that :-) >>>>> We use it for everything, never had a problem either. >>>>> >>>>> I take "no-clean" to mean "do not clean". I have heard (here) of >>>>> problems when cleaning is attempted, the insulating component is washed >>>>> away leaving an ionic residue which can absorb water and conduct. Or >>>>> something. >>>>> >>>> Even then I had no problems. Many times in my lab I lash up jigs, on >>>> Monday for example a tester to run transformers at 50Hz, 60Hz, 400Hz or >>>> wherever. That stuff gets a beating over time, alligator clips are >>>> attached to soldered areas over and over again so things become scraped. >>>> Never a problem. >>> Try it for high impedance circuits >> 1E7 Ohms. >> >> I avoid that wherever possible. If needed it's best to work with guard >> rings. > > So do i, still, i did enough stuff at 1E8 Ohms and some much higher > (1E12 Ohms) to have a real respect for doing that routinely. Ok, but that's a specialty area. There will always be specialty areas where normal design techniques aren't good enough. All I am saying is that IME No-Clean is quite ok for all the regular designs I did. And this has included some hardcore low-noise stuff. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |