Need Help on DIP IC Sockets for Hardware Projects

[MueThor]

Hi folks,

 

As CC Clarke had written in an earlier post in the thread "console speedup mod" for experimenting with hardware socketing is recommended. In this context I have now many questions. Which technical data has to be fulfilled by a socket to be soldered onto the TI board? There exist different DIP sockets for IC with different specifications for pitch, row width, contact resistance, contact material and contact plating. I will have to buy DIP IC sockets with rectangular pitches, but with which row width (0.3" or 0.6")? Is a maximum resistance for the contact resistance of 20mΩ okay? Are copper alloy as contact material and tin for the contact plating enough? Please, can anyone of you guys answer my questions, also with regard to very long lasting and stable socket solutions?

 

 

Regards

Edited March 17, 2017 by MueThor

[Meddler]

Well, obviously you have to buy sockets that match the I.Cs that you want to fit i.e 18 pin, 20 pin, 24 pin etc. and width to suit. All these details will be on the data-sheets.

From experience, you get what you pay for though "turned-pin" are superior in all cases and probably worth the extra expense for your requirements.

Edited March 18, 2017 by Meddler

[+Ksarul]

You definitely want turned-pin (also known as machine pin) sockets. Most of the ICs in the TI have pins set .100 in (2.54 mm) apart, set on a .300 wide socket frame. There are some chips that need the .600 wide frame--but they use the same pin separation as the rest of the chips on the board. The only chip I have seen on a TI using a .400 wide frame is used for the Hex-Bus controller, so you shouldn't be needing any of those.

 

I usually try to get the sockets with gold-plated pins (on many machine pin sockets only the inserts are gold plated), as they tend to solder better and they don't tarnish over time.

 

Sorry for the slow answers this week--I've been in and out of hospital a couple of times since Monday for some gnarly (Groß, Fies, und Hartnäckig) kidney stones. . .and the next week will be worse.

[MueThor]

Hello guys,

 

So for a 24-pin TI DIP IC following socket would be suitable?: http://www.ebay.com/itm/24-PIN-MACHINE-TOOLED-IC-SOCKETS-GOLD-INSERT-QTY-10-NEW-/201822691356?hash=item2efd91e01c:g:mekAAOSwfC9XPNnf. There in the ad it is stated that the socket is of 300 Mil type. What does the latter specification mean? For what does Mil stand for? If it stands for millimeters, then this socket is possibly the wrong type for my application. Or is hereby a .300 (inches?) wide socket frame specified the one to be chosen according to Ksarul?

 

I would be delighted, if anyone of you answered my new questions.

 

 

Best Regards

Edited March 19, 2017 by MueThor

[Osgeld]

mil is thousands of an inch so 300 mil = 0.3 inches (i personally hate that phrase I use thou, cause its a thousandth of an inch)

Edited March 19, 2017 by Osgeld

[+Ksarul]

Mil is generally a machinist's term, and as noted, it is thousandths of an inch. A 24-pin socket will usually be a .600 socket on a TI. To figure out if you need .300 or .600, look at the chip. If the chip is thin (skinny), you need the .300 sockets for it. If it is wide when compared to the skinny ones on the board, it is a .600 socket. The visual check tells you everything you need, as you just count the pins and you have the rest of the answers for the socket.

[ElectricLab]

The term "mil" is used in PCB design lingo as well.