[neonixie-l] Re: IC Sockets
Thanks to everyone who replied to my question. The consensus is that I should probably not use sockets unless the design calls for them, so that's what I will do. As someone mentioned, once I realized that I had nothing to lose by destroying the bad part and removing it in pieces, I've caused little or no damage. However, some of the boards that I have messed up seemed too delicate (or cheap) because the traces lifted very easily. I've had a Soldapullt for many years, and it is one of my most useful tools. Jim -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/dfc8c080-f014-3015-d852-2d2f6c16482d%40earthlink.net.
Re: [neonixie-l] Re: IC Sockets
Dont use IC sockets; they are not necessary. If the circuit is properly designed, meaning that all IC datasheet parameters are met, you should never see an IC fail. I've built many nixie clocks, all of which I designed, and I've never had an IC fail on it's own. The first failure I've had was a few weeks ago, caused by ESD (my fault) on a Raspberry Pi, so technically not one of my designs. IC's are actually easy to remove without damaging the PCB, though you will likely destroy the IC in the process. For thru-hole IC, flow fresh solder into each pin, and while it's still molten, use a vacuum desoldering tool like the Edsyn Soldapullt (see below). I've been using mine for ~40 years now, and it still works great. Once the pin is sucked-out, wiggle it with the soldering iron and it should be free. Once all pins are cleared, you should be able to gently wiggle the IC out with your fingers. If not, snip the stuck pins off the IC with fine clippers, then use tweezers to remove the pin while heating it. After all pins are clear, mop-up with some solder wick, then clean with 90% isopropyl alcohol. PCB should be just-like-new. SMT parts need careful heating with a hot-air reflow tool, and you should be able to gently lift it with tweezers, though some pins will get bent and most likely the IC has been thermally overstressed, so toss it away. Clean-up is same as above. Lastly, I never breadboard a design. PCBs are easy and cheap to have fabbed, and have far superior quality. If you mangle a board with debugging, build another. But if you do proper simulation beforehand designing the PCB, you wont need to do any debugging. https://www.edsyn.com/product/DS017.html On Saturday, February 18, 2023 at 4:48:33 PM UTC-8 Charles MacDonald wrote: > > something in a high vibration environment like a vehicle will give you > > more problems. Corrosion is another 'issue'.. but if it's that bad you > > should be coating your boards anyway. > > back in the 70s I delt with Apple ][ Computers that used socket-ed DIP > ICs problems Noted: > > bad contact - corrosion. > loose IC due to vibration. > they went for Premium AMP brand sockets to get better retention and some > of the ICs left the factory with one or more the pins bent under. this > worked at first, BUT made for Flaky INTERMITTENT contacts. > > Also the socket will have more capacitance then just a plain PC Board, > which might round off your signal edges. I think we even had one board > where the larger area of the contacts caused a solder bridge, and > pulling the socket was more difficult than just pulling an IC would have > been. > > -- > Charles MacDonald VA3CPY Stittsville Ontario > cm...@zeusprune.ca Just Beyond the Fringe > No Microsoft Products were used in sending this e-mail. > > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/a9ef20f3-25c5-4f7b-870b-b49e6389a280n%40googlegroups.com.
Re: [neonixie-l] Re: IC Sockets
something in a high vibration environment like a vehicle will give you more problems. Corrosion is another 'issue'.. but if it's that bad you should be coating your boards anyway. back in the 70s I delt with Apple ][ Computers that used socket-ed DIP ICs problems Noted: bad contact - corrosion. loose IC due to vibration. they went for Premium AMP brand sockets to get better retention and some of the ICs left the factory with one or more the pins bent under. this worked at first, BUT made for Flaky INTERMITTENT contacts. Also the socket will have more capacitance then just a plain PC Board, which might round off your signal edges. I think we even had one board where the larger area of the contacts caused a solder bridge, and pulling the socket was more difficult than just pulling an IC would have been. -- Charles MacDonald VA3CPY Stittsville Ontario cm...@zeusprune.ca Just Beyond the Fringe No Microsoft Products were used in sending this e-mail. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/db32f8fc-fb0e-28e4-533a-79c74bb97b05%40zeusprune.ca.
[neonixie-l] Re: IC Sockets
Jim, I agree with Mac, one downside to sockets is some tend to come loose. It is mechanical retention after all, and at times with questionable quality sockets. Not usually a problem with stationary electronics, something in a high vibration environment like a vehicle will give you more problems. Corrosion is another 'issue'.. but if it's that bad you should be coating your boards anyway. Vintage stuff tends to be problematic at times, ICs that have been sitting in a socket for 40 years may not be making the best contact. Most low frequency signals, KHz, a few MHz for example, should be fine with a socket. Sensitive feedback circuits, for example on a DC-DC switching IC, I would not put in a socket. I usually use sockets on a prototype where I think I may need to swap parts, or the likelihood of destroying an IC during testing is high. Otherwise modern stuff is so reliable these days, if it's a production PCB or part that I know I'm not going to mess with, I won't use a socket. Modern integrated circuits, if used within their design limits, will last decades. I've been doing this for a while, and some stuff is just difficult to desolder without damage, that's how you learn PCB trace repair! :) Regards, -Moses On Saturday, February 18, 2023 at 3:26:06 PM UTC-8 Jim KO5V wrote: > I've built many electronics projects over the years, and most of them have > actually worked. However, I am an ME, so my actual knowledge of electronics > is a bit spotty, and most of my ham radio experience is not with TTL level > stuff. > > I would like to use IC sockets on my current clock project, but this > design does not call for using them everywhere. I've had to unsolder a few > ICs in the past, and the PC boards have almost always suffered, sometimes > requiring some really ugly repairs. > > So, is there a reason other than saving a few parts for not using the IC > sockets - like added paths for noise, or?? > > Thanks in advance. I hope this isn't too stupid a question! Jim > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/fb1baff9-1bfb-43b2-8d94-db0ad4c95cf7n%40googlegroups.com.
