ZIF sockets - need a really high quality one for an EPROM programmer - Page 1
Forum section: electronics / beginners

author: SolderSucker
author_rank: Regular Contributor
timestamp: May 21, 2020, 11:06:31 am
content: I do a lot of work on older PCBs which have thru-hole and often socketed chips and on a daily basis need to re-program EPROMs.One major annoyance that I have is ZIF sockets and inserting EPROMs - more often that not, even if the legs on the EPROM look perfectly aligned it's a major fiddle to insert them into the ZIF socket, if one is out just a fraction of a millimetre it can prevent insertion. I can sometimes waste a minute or two minutely and repeatedly tweaking the legs and trying to insert an EPROM into the programmer's ZIF socket before it finally fits.I've noticed this on different programmers too.(Note: when I mention tweaking the legs I'm referring to those legs next to each other, so 1 to 2 to 3 to 4, etc - not those opposite each other).Naturally, the larger the EPROM the more of a hassle it often is.So I'm wondering if there's a really high quality ZIF socket out there which I could put into the programmer's ZIF socket (or I could desolder the original ZIF and replace it).Or maybe there's some tool to 100% straighten the legs of thru-hole parts like EPROMs? I know about the leg straighteners that are basically two sealed bearings in a slab of metal, but I need to straighten those legs that are next to each other, not those that are opposite.

author: ebclr
author_rank: Super Contributor
timestamp: May 22, 2020, 11:41:10 am
content: If you are not happy with ZIFThis maybe will make you happy.https://www.zeitech.de/CPT-058-IC-DIP40-Test-Clip-headIt's another approach using the top of the legs, not the bottom

author: SolderSucker
author_rank: Regular Contributor
timestamp: May 22, 2020, 11:48:06 am
content: Ah yes, I remember seeing those years ago. Might not be 'fun' incorporating that into an EPROM programmer though ...........

author: greenpossum
author_rank: Frequent Contributor
timestamp: May 22, 2020, 11:58:07 am
content: Wouldn't it be better to get a straightener which will also help putting the chips back into the sockets afterwards?

author: SolderSucker
author_rank: Regular Contributor
timestamp: May 22, 2020, 12:17:04 pm
content: Quote from: greenpossum on May 22, 2020, 11:58:07 amThe only straightener that I know of will only straighten the legs on the opposite side of the EPROMs, and that's not the problem - it's the legs right next to each other which are the issue and, even if a fraction of a millimetre off, will cause problems when inserting into a ZIF socket. The bigger the EPROM the more problems there are.

author: Benta
author_rank: Super Contributor
timestamp: May 22, 2020, 06:05:31 pm
content: I've always been very happy with Textool ZIF sockets.https://www.digikey.de/products/de/connectors-interconnects/sockets-for-ics-transistors/409?k=textool

author: SolderSucker
author_rank: Regular Contributor
timestamp: May 22, 2020, 06:32:10 pm
content: Thanks!

author: MarkF
author_rank: Super Contributor
timestamp: May 22, 2020, 06:59:23 pm
content: I use these for both wide and narrow ICs in my programmer:https://www.digikey.de/product-detail/de/3m/240-1288-00-0602J/3M4006-ND/229812

author: SolderSucker
author_rank: Regular Contributor
timestamp: May 22, 2020, 07:10:31 pm
content: Thanks!

author: greenpossum
author_rank: Frequent Contributor
timestamp: May 23, 2020, 12:38:04 am
content: Quote from: SolderSucker on May 22, 2020, 12:17:04 pmOn the programmer I have the ZIF socket look like the ones above and are tolerate a small deviation. If the offset is so large that the devices don't fit in the ZIF socket I wonder how you manage to plug them back on the board.

author: james_s
author_rank: Super Contributor
timestamp: May 23, 2020, 06:14:42 am
content: The Textool sockets are nice. Honestly though even the ones that have got to be fakes that you can get for just a couple dollars from China seem to work fine too, I can't think of a time I've had trouble getting an IC in when the pins were straight enough that I could get it into the sockets on the board it was going to be used on. There is one type of ZIF socket that has rather narrow openings but I've mostly used the wide slot ones that will take either .300 or .600 ICs, those offer loads of wiggle room.

author: SolderSucker
author_rank: Regular Contributor
timestamp: May 23, 2020, 09:16:21 am
content: Quote from: greenpossum on May 23, 2020, 12:38:04 amAs noted in my original post:"if one is out just a fraction of a millimetre it can prevent insertion"

author: ogden
author_rank: Super Contributor
timestamp: May 23, 2020, 10:06:33 am
content: Quote from: SolderSucker on May 23, 2020, 09:16:21 amCan't be. Even DIP sockets allow bigger pin intolerances. Did you notice lever in one end of the ZIF socket?Usually contact openings are wide enough to accept very abused DIP IC's:

author: SolderSucker
author_rank: Regular Contributor
timestamp: May 23, 2020, 10:39:14 am
content: Trust me, when you have a number of pins even slightly out of whack, especially on a large chip, even wide ZIF socket tolerances go out of the window. I've been programming up a lot of (used) 42-pin EPROMs lately and many are a real swine to get into a ZIF socket even though the pins LOOK perfectly aligned.I'm no noob at this either, I've been programming EPROMs for 30 years, I've just never been arsed to look into 'better' ZIF sockets before. It was the 42-pin EPROMs that finally drove me over the edge.

author: Gyro
author_rank: Super Contributor
timestamp: May 23, 2020, 11:39:14 am
content: I'm a bit confused. I've generally found that IC sockets are far more critical that ZIF sockets for pin alignment when inserting. Is it actually your EPROM removal method / tool that needs improvement?I never had any problems with the wide slots in Textool sockets either.

author: Electro Fan
author_rank: Super Contributor
timestamp: May 23, 2020, 06:23:52 pm
content: Quote from: Gyro on May 23, 2020, 11:39:14 amSame here. The step that usually needs the most care and skill is removing an IC without bending pins. Inserting ICs requires a bit of patience and aim whether on a PCB or in a ZIF/programmer, but the insertion generally goes well if any prior extraction went well.Having said that, the more pins the more precision that is required. I'm looking at a TL866 and I think it only has 40 slots on the ZIF, so I guess as the ICs get longer with more pins more attention to alignment is required.

author: ogden
author_rank: Super Contributor
timestamp: May 23, 2020, 06:32:45 pm
content: Quote from: SolderSucker on May 23, 2020, 10:39:14 amSo what. Perhaps all those 30 years you are doing something wrong with either DIP ICs or ZIF sockets. Could you provide macro photos of what you are talking about? It is hard to believe, many would like to see.

author: helius
author_rank: Super Contributor
timestamp: May 23, 2020, 07:07:59 pm
content: Another DIP ZIF socket manufacturer is Aries. From the ones I've seen, they are equal quality to Textool.For QFP ZIFs you can go with Yamaichi.

author: Electro Fan
author_rank: Super Contributor
timestamp: May 23, 2020, 08:41:17 pm
content: Quote from: helius on May 23, 2020, 07:07:59 pmThankshttps://www.arieselec.com/products/data/10001-universal-dip-zif-test-socket.htmAries Universal Test socket accepts devices on 0.300 to 0.600 [7.62 to 15.24] centersThe Aries ordering information tool makes it easy to find the part number for the preferred configuration.Just use the drop down menu to specify your preferred Pin Count, Row to Row Spacing, Handle Options, and Plating:pdfs are still good for more info/more detailed specs but the ordering tool is pretty nice.https://www.arieselec.com/products/data/10001-universal-dip-zif-test-socket.pdf

author: helius
author_rank: Super Contributor
timestamp: May 24, 2020, 05:25:09 am
content: Another point that may get overlooked is that the ZIF socket on a programmer is a wear item: it may be rated for 10,000 insertions, but the programming cycle is short, so it still can wear out in a few years of heavy use. The ZIF sockets have spring fingers that press-fit into a collet socket underneath to facilitate replacement. They may also be available with "solder tails", so check the datasheet before you order.