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I've designed some PCBs where I have a socket for a Teensy 3.2. The exact sockets I purchased were these turned pin open frame sockets. I also purchased these turned pin headers to solder to the Teensy.

This works great, however the Teensy is really hard to remove without bending the header pins. Obviously a certain amount of force is required to remove the Teensy. Are there any tools that would help or a particular recommended method?

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People will probably disagree, but I just use a screwdriver, its all about going slowly. I use a flat head, slip it between the chip and the socket then twist it slightly, then change ends and do the same, if you go in small increments you will be fine. Don't just try and do it all from one end.

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    \$\begingroup\$ I'd disagree with the extractor tool more than with a scredriver, never managed to get an IC straight out of its socket with that thing... \$\endgroup\$ – Arsenal Apr 21 '17 at 14:22
  • \$\begingroup\$ @Arsenal Are you referring to the "pincers" style nightmare extractors, or about the tool from my answer that I never came around to try myself? \$\endgroup\$ – Marcus Müller Apr 21 '17 at 14:28
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    \$\begingroup\$ @MarcusMüller pincers style nightmare. Never seen that crazy high quality tool you posted - seems like it could do the job right. \$\endgroup\$ – Arsenal Apr 21 '17 at 14:32
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    \$\begingroup\$ "high quality": $21.75 retail price :) That's why I'm a bit careful recommending it... \$\endgroup\$ – Marcus Müller Apr 21 '17 at 14:34
  • \$\begingroup\$ +1 Back in ancient times when every chip was socketed, I removed many chips using this method. \$\endgroup\$ – Paused until further notice. Apr 21 '17 at 19:28
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There's really pesky cheap "IC extractors" that work worse than simple screwdrivers, and then there's these things, that I never cared to buy because I never had many ICs to remove from sockets, so I don't know how well it works:

https://www.jensentools.com/ok-industries-ex2-dip-extractor-for-24-to-40-pin-wide-body-chips/p/606mi026

extractor

I'm sure they're available through different channels, but they do look like they would help lift something very straight.

EDIT Peter says below it works well.

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  • \$\begingroup\$ FWIW I've never had a problem with IC extractors - they always made it easier to get chips out of a socket without the inevitable pin-bending from a screwdriver. Of course there are probably bad ones, but I used something like this: maplin.co.uk/p/ic-extraction-tool-fd54j \$\endgroup\$ – Graham Apr 21 '17 at 16:08
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    \$\begingroup\$ I used one like Marcus shows to pull UVPROMs for re-programming - worked well for that application. \$\endgroup\$ – Peter Bennett Apr 21 '17 at 16:09
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    \$\begingroup\$ I have used these too, and when used properly they work pretty well. Sometimes though you need to use quite a bit of force and then the chip pops out suddenly with a quite a shock which I did not think was particularly good for the board. Other issue with them was, they need to be lined up just right or they pop off the end of the IC and can actually damage the laminated variety. That and I could never find it when I needed it, simple trusty screwdriver was always at hand. \$\endgroup\$ – Trevor_G Apr 21 '17 at 16:27
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    \$\begingroup\$ These tools are absolutely the right way to remove ICs in a production environment. They hold the IC firmly against a ledge and the hooks allow the IC to be pulled straight up. If you have many ICs adjacent on a board then a screwdriver may not work, and it always results in the IC having a greater angled side force applied. \$\endgroup\$ – Jack Creasey Apr 21 '17 at 16:54
  • \$\begingroup\$ Perhaps for an IC, but it's unclear that these will fit the PC Board Module that the question is about. The pins may match a 28 pin 600 mil EPROM, but the mechanical shape is different. \$\endgroup\$ – Chris Stratton Apr 9 '19 at 19:17
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With the power off, use a fine-bladed screwdriver. Start at one end and lever that end up just a bit. Go to the other end and lever it up a bit further. Alternate ends and eventually it will come free.

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I also agree with the "use a flat screwdriver, carefully, alternating ends" answers.

"Back in the day" Heathkit would include with (at least some of) their kits that used integrated circuits a small metal L-shaped tool, about two inches long on the long leg and maybe half an inch on the short leg, for precisely this purpose. They had the same "start at one end of the IC and lift it a little, then go to the other end and lift a little, until the IC is free of the socket" method.

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The screwdriver is pretty reliable but in some situations it is not possible to gain access to the ends of the chips.

The go-to tool in the day was a pair of DIP IC extractor tweezers/tongs such as those sold by Jameco even now.

However these would often cause the IC to pull out suddenly as one end came free and cause the pins to bend or break, it was best used with the hand resting on the board and levering the hand against the board to control the extraction.

What I found the best was a simple L-shaped bit of sheet metal that was supplied by some DIP DRAM suppliers in the early IBM PC XT days. It was slipped in the end of the IC on both sides and then rocked forward and back to raise the IC in small controlled steps. The lever action was so large that sudden extraction was rare and the multiplied force would free even recalcitrant chips. I have not seen them for sale ever but they can be easily made and look pretty much like a simple lock-picking torquing wrench (the one on the left is close to form). They should not be much wider than 5mm or the control is lost, they need to have a bit of width just for mechanical strength, perhaps 3mm would be enough. The bend is only about 1.5 to 2.5mm long so it can slip between close spaced components. Use the thinnest metal strip you feel will be strong enough for the job, the lock-picking fraternity use the backing strips in some types of windscreen wiper blades and this may be just what is needed.

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    \$\begingroup\$ Back in the days when PCs used ISA-bus connectors, cases usually came with L-shaped piece of metal to covered the exterior openings associated with unused slots; those pieces had a notch in the short leg to screw them into the case, and that notch was placed perfectly for lifting 0.3" DIPs out of sockets. \$\endgroup\$ – supercat Apr 21 '17 at 23:07
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TWO screwdrivers, one each side.

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    \$\begingroup\$ brilliant, but with one caveat: it requires the DIP chip to not be inserted too tightly already; otherwise, an attempt to put one screwdriver on one side will make putting the other one impossible, due to the tilt & resulting lack of space. \$\endgroup\$ – user20088 Apr 22 '17 at 22:19
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If you really need to do this, you have several options.

First of all, the turned pins and round sockets you are using are the most difficult to take apart. You might consider trying sockets that can accept the more typical square cross-section pins that Paul ships with the Teensy. The socketing image below is not of the Teensy 3.2, but of another board that has the same profile:

enter image description here

With this type of socket it is slightly easier to use a screwdriver or L-iron to lever out the Teensy. However, the truth is that levering the Teensy first from one end and then from the other will always cause slight bending of leads, even when it is imperceptible. To prevent this, you will need to lift directly upwards, with no tilting component to the motion.

For strict upward pull, the Jenson extractor suggested by Marcus Muller works quite well, and will not bend pins. I've always been able to find mine when I needed it :) However, the Teensy has a USB port on one end that protrudes slightly beyond the board edge, and this will interfere with the end gripper, which is designed to fit an actual chip rather than a daughterboard masquerading as a chip.

Another alternative is to place a thin strip of stiff material between the Teensy and the socket, allowing it to protrude slightly at each end. This allows you to lift while rotating it to lever the Teensy gently from side to side, rather than from end to end, resulting in much less likelihood of noticeably bent pins.

The other option for you is a ZIF connector. All models I've ever seen will accept any pin profile -- even fragile leaf pins grabbed sideways. I use the traditional square-profile headers in mine. The turned pins you have been using will work, but the contact area will be less than with the square pins.

I'm not familiar with Jameco or the very interesting shipped-from-china model suggested by X Goodrich, but the 28-position 0.6" row spacing 3M models available from DigiKey and Mouser are about $25 at QTY one.

ZIF sockets of the type we are discussing are really designed for use in programming and prototyping, and are not designed to hold chips or daughterboards in the field. For one thing, the use of a ZIF socket requires more room on your board in all three dimensions. For another, the gripping / contact force is sufficient for benchtop work, but nowhere near what is provided by a fixed-insertion-force socket.

Also, I caution you that some ZIF sockets do not really "lock" properly in the closed position. When deploying field prototypes I have had chips dislodged in the field, and I've sometimes had spurious contact issues. If this matters to you, you may need to look at several different models. Here's a link to the full list of ZIFs available at DigiKey:DigiKey ZIFs

enter image description here

Above is the super-inexpensive ZIF socket from china that's being sold on eBay. Although the mold is labeled 3M, I'd be surprised if it was really a 3M product. I'm definitely going to order some, but from this photo it doesn't appear that the contacts are gold-plated, and if not, they would be corroded fairly quickly in Hawaii, where I live :)

Here is a larger, 40-pin ZIF socket that's also super-inexpensive ($4) from AdaFruit:

enter image description here

Again, I don't know how they manage that price unless this is a knockoff, because this is labeled with a 3M part number that indicates the clamping faces will be gold-plated.

Mostly, though, I would be interested to know what you are doing that requires you to remove and replace the Teensy 3.2 daughterboard. I've done a number of designs with that board, and since it is field-programmable I have never come across a need for removal and replacement in the field. Can you explain what you are trying to accomplish by socketing it in the first place? Perhaps we can suggest other options that might be useful to you.

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  • \$\begingroup\$ Thanks for the informative and interesting answer! I've designed a PCB for a midi controller that connects to two computers simultaneously in order to send identical commands. The easiest method I found to do this was using 2 Teensy 3.2s. I am open to redesigning the board and trying another way, although I didn't feel confident enough and nor do I have the tools to put the whole design of a Teensy on my PCB. The reason for the sockets is once the Teensy is soldered to the PCB it is near impossible to remove... i.imgur.com/a3lkNwp.jpg \$\endgroup\$ – CircularRecursion Apr 23 '17 at 12:21
  • \$\begingroup\$ The socket in your first image is not designed to take a square pin. It's designed for flat IC pins only, and using them with the typical square pins will damage the socket. That doesn't keep people from doing it (same with breadboards, really), but I do not like how it's phrased here. \$\endgroup\$ – pipe Apr 23 '17 at 15:55
  • \$\begingroup\$ Pipe, thanks for pointing out that square pins are going to overflex and ultimately damage a socket (or breadboard) that was designed for IC pins. In real life that matters for breadboards, which will no longer make tight contacts with flat IC pins after you use square pins in them for awhile, but it doesn't really cause a problem if you have a single daughterboard that's being removed and replaced from its socket. Another alternative is to use stacking headers rather than actual sockets -- they are designed for square pins right from the start. \$\endgroup\$ – Craig.Feied Apr 24 '17 at 7:40
  • \$\begingroup\$ @CircularRecursion, a lot of people use Teensys for midi control, so you probably aren't too far wrong, though I'm not sure why you'd need more than one to send simultaneous midi messages to multiple computers -- the Teensy 3.2 can connect to 4 (or 5) serial devices simultaneously, and commands being sent to all serial ports in a main loop would all get sent within a single loop cycle of about 5 - 15 microseconds, which is as close to simultaneous as you're going to get when dealing with multitasking operating systems on PCs :). \$\endgroup\$ – Craig.Feied Apr 24 '17 at 7:49
  • \$\begingroup\$ @CircularRecursion, My question was really about why you would need to remove a Teensy once it was soldered onto the PCB. Since the Teensy can be reprogrammed while on the PCB (via the USB port) I've never had a need to remove one from a development board unless the board broke or I was redesigning it. Are you doing something special that requires your Teensys to come on and off? \$\endgroup\$ – Craig.Feied Apr 24 '17 at 7:50
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I suggest a ZIF socket, if you find it economical and have room to fit it. This is what I did (and I assume many people do) with programmable microcontroller boards.

This 28-pin wide socket at Jameco costs USD 10, but on eBay ones I think are even better are about USD 3.25 (single piece) including shipping (which may take a few weeks).

Jameco: https://www.jameco.com/z/28-526-10-Aries-Electronics-Connector-ZIF-Socket-SKT-28-Position-2-54mm-Solder-Straight-Thru-Hole_102745.html

eBay (2017-04-21): http://www.ebay.com/itm/28P-28-Pin-2-54mm-Universal-Narrow-Wide-ZIF-Test-DIP-IC-Socket-Connector-/231871394699

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  • \$\begingroup\$ What pins would you suggest I solder to the Teensy? \$\endgroup\$ – CircularRecursion Apr 21 '17 at 22:15
  • \$\begingroup\$ I was hoping you could put 28 legs onto the Teensy, along the two major outer rows, and solder a ZIF socket into the board, so that the Teensy could be inserted / removed from the socket on the board with just a flip of the ZIF lever. (I see that a Teensy has at least a third side of connections, and I don't know anything about connecting those.) \$\endgroup\$ – X Goodrich Apr 22 '17 at 4:36
  • \$\begingroup\$ This project is only using the two outer rows. That's why I managed to use the frame linked in my original question! What kind of legs should I be looking for to fit a ZIF socket? \$\endgroup\$ – CircularRecursion Apr 22 '17 at 16:52
  • \$\begingroup\$ ZIF sockets are meant for the same kind of legs as PCB through-holes and push-in sockets, as far as I know. Alas, I am not knowledgeable in the differences between profiles for component legs. Perhaps that would best be handled with a new question? \$\endgroup\$ – X Goodrich Apr 24 '17 at 16:45
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I agree with the "screwdriver" answers. Just be careful and alternate between ends. Don't try to lift one end all at once.

Also, the turned-pin headers/sockets are much tighter than the standard, lesser expensive sockets/headers with the flat legs.

I'll post some images later today, in case you don't know what I'm referring to.

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