DIP through-hole chips are an old package with instantly recognizable dual in-line pin rows. Beginners love these chips because they’re large and look easy to solder; we abhor them because we hate messing around with the drill. Whatever your motivation for using a through-hole chip, use a socket whenever possible. A circuit board with socketed chips is easy to test without endangering the parts, and ICs can be removed, tested, and replaced, without resorting to a soldering iron. This week, by request, we looked at several common through-hole chip sockets.
DIP sockets are available in almost any pin-count, or you can use individual strips to make a custom size (Mouser #40-0518-10). ICs with less than 40 pins usually have .300″ row spacing, but many 40+ pin ICs are .600″ wide. Footprints are included in the Cadsoft Eagle default ic-package library as DILxx. Below is a list of our most commonly used DIP sockets.
8 pin .300″ socket (Mouser#571-1-390261-2, $0.14) This socket is useful for op-amps and small microcontrollers, like the 12F629 used in the Esquire e-paper cover.
14 pin .300″ socket (Mouser #571-1-390261-3, $0.15) Another small socket we occasionally need.
18 pin .300″ socket (Mouser #571-1-390261-5, $0.18) A very common chip size for lots of microcontrollers and 7400 series parts
28 pin .300″ socket (Mouser #571-1-390261-9, $0.30) Another common size for through-hole microcontrollers, and chips like the TLC5940 16 channel pulse-width modulator. Check your datasheet because a .600″ row spacing 28 pin DIP package also exists.
40 pin .600″ socket (Mouser #571-1-390262-5, $0.41) Watch out, this is a wide socket for chips with .600″ row spacing. Fits common 40 pin chips, like the PIC 18F4455 USB microcontroller.
Don’t forget to check out our previous parts posts.
I always buy whatever size (14-28) surplus sockets I can find, and if I need a size I don’t have laying around I’ll cut rows off two sockets until I have the size I need. It might be a bit wasteful, but the sockets I buy are usually production run surplus anyway.
If you have to remove an ic often, for example when you’re programming a microcontroller without using iscp, get two sockets of the expensive kind, place one on the pcb and place the ic in the other.
This makes removing the ic from the pcb much easier.
the expensive kind of socket comes very handy for homemade double-sided PCBs, because you can solder under them. there is some space between the frame and the board surface where the socket pins are reachable with a soldering iron. When you have to make via connections under IC pins, this is an elegant way to do it.
Jan
Just want to say I really dig these posts on parts. The comments are as insightful as the original posts. Thanks.
I never solder ICs directly; sockets are great, plus for the home-brewer, it allows room for mistakes – just pull and replace the IC.
For building programmer boards, I can’t find ZIF sockets locally and the usual suppliers seem a bit expensive. For a good resource, Chinese vendors sell on eBay and I’ve had good results. I can get 6 or 8 ZIF sockets delivered from Hong Kong to Texas in about 8 or 9 days.
I like single inline sockets (ex Digikey pn: ED7064-ND). Just cut off the number of pins you need.
Sockets are an absolute must for any prototype application. Don’t cause yourself more problems then necessary. Using sockets is like saving often in Word.
or enabling the autosave frature in openoffice :)
Anyway, these are a must for 40 pin micros like the PIC, (definately dont want to waste solder wick on one of those). especially if you don’t have icsp like me and my cheap self built one
Keep in mind though these sockets wear out, and things like comparators and op-amps and other analog parts that are very sensitive to signal inputs can give you faulty responses after a few too many uses.
-Taylor
Is hackaday turning into an online shopping network ?
Id just like to say, these parts are way overpriced.
$0.41 for a 40pin socket at mouser
or
$0.18 for the same at http://www.futurlec.com.au
I do appreciate the parts articles over the past few weeks. I think it’s a fantastic idea that brings up some very fundamental issues.
However, my one complaint about the parts articles has to do with the follow-through, that they don’t go quite deep enough into the given topic. For instance, on this post it would have been very nice in this article to mention the difference between machine pin sockets and the spring-action sockets pictured above. It would have been nice to at least mention zero-input force (ZIF) sockets for applications where easy extraction is much more important than board space. It might have even been worthwhile to mention something about more complex sockets for higher pin count chips, and I could probably ramble on.
I have similar criticisms of the stereo jack article, the microSD card article, etc. I think that the LM317 article had the best background information (or at least links to helpful calculators, etc).
I think you guys are doing a very good thing by including these parts articles as a reoccurring type. However, I think you could improve them greatly by adding a little more substance (background, implementation, schematics, links to sample code or projects, etc).
~ben
All the ICs in the pic are the terrible wiper-contact sockets. I like those expensive ones with the rows of holes.
As others said too, the sockets illustrated in the above picture are the worst type. Best ones, with rows of holes (gold or silver), named by others “expensive ones” are named AUGAT (google for augat sockets)
Does anyone know of a DIP 40 Eagle part? Thanks.