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Thin pin headers for "piggy-back" boards

Posted: Mon Jul 22, 2024 7:35 pm
by GlennSmith
Hello all,
I'm working on a couple of ideas for "piggy-back" PCBs that can be plugged into the 40-pin DIL socket in place of a 65C02 processor.
[One of them is my CPLD board that creates a user-stack space and a user "page zero" using some "undocumented" NOPs]
While I'm waiting for my proto PCBs to arrive, I've been trying to find some 0.1" pin headers but with THIN pins that can be plugged into standard DIL sockets (not tulip ones) without unduly forcing them - so I can revert back to putting the uP back in it's place if needed.

So, my question : what do I look for on Mouser or Farnell ?

Some of my Arduinos came with some neat socket headers with long pins
Arduino_Header.jpg
which would be perfect, but I don't have enough of them... What are they called ? (No, I'm only half forgetful - remember I've lived and worked in France for ~40 years and some jargon I never actually learned in English...)

Any hints (or links) would be welcome :)

Re: Thin pin headers for "piggy-back" boards

Posted: Mon Jul 22, 2024 8:04 pm
by barnacle
https://www.jameco.com/webapp/wcs/store ... 2144631_-1

These may be what you're looking for? The key words are 'long tail' - though Digikey has very little showing.
2144631.pdf
(119.04 KiB) Downloaded 56 times
Neil

Re: Thin pin headers for "piggy-back" boards

Posted: Mon Jul 22, 2024 8:14 pm
by barnacle
Alternatively, search ebay for arduino prototyping boards; many of those come with a set of feed-through sockets (but be careful; not all!)

e.g. https://www.ebay.de/itm/155885314173

Neil

Re: Thin pin headers for "piggy-back" boards

Posted: Tue Jul 23, 2024 12:20 am
by BigDumbDinosaur
barnacle wrote:
https://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2144631_-1

These may be what you're looking for? The key words are 'long tail' - though Digikey has very little showing.

Those will not safely plug into a DIP socket.  Something like the attached might work.

stacker_pins_samtech.pdf
Stacker Pin Sets
(179.54 KiB) Downloaded 68 times

Re: Thin pin headers for "piggy-back" boards

Posted: Tue Jul 23, 2024 7:54 am
by GlennSmith
Thanks guys!
I've found a few possibilities at Mouser, mainly from Samtec, similar to the ones proposed by BDD. My worry though is that the pins are 0.6mm dia. (Edit - just saw that they're 0.4mm also) :)
The ones in my photo, and proposed by Barnacle, do work with the DIP sockets that have wide, flat, connection surfaces. At only 0.4mm thick, the pins don't damage the sockets. Unfortunately Mouser don't have those. So I'll order a few samples and see how it all works.

Re: Thin pin headers for "piggy-back" boards

Posted: Tue Aug 13, 2024 9:23 pm
by Osi
GlennSmith wrote:
Thanks guys!
I've found a few possibilities at Mouser, mainly from Samtec, similar to the ones proposed by BDD. My worry though is that the pins are 0.6mm dia. (Edit - just saw that they're 0.4mm also) :)
The ones in my photo, and proposed by Barnacle, do work with the DIP sockets that have wide, flat, connection surfaces. At only 0.4mm thick, the pins don't damage the sockets. Unfortunately Mouser don't have those. So I'll order a few samples and see how it all works.

Hi Glen,
for my piggy-back boards I'm using the following combinations.
The shown socket header (I prefer the gold-plated versions) comes with 0,36mm thickness (typical) and fits perfectly into the mentioned sockets. Also, the socket contacts do not get stressed and afterwards, the IC will go back in nicely.
A standard pin header goes into the PCB. When the socket headers are pre-inserted into the socket, it is quite easy to plug/unplug the PCB on top.

Socket.JPG
Socket Header
https://www.we-online.com/de/components ... 130XX11821

THT Pin Header
https://www.we-online.com/de/components ... 1300511121

Thomas

Re: Thin pin headers for "piggy-back" boards

Posted: Tue Aug 13, 2024 11:07 pm
by plasmo
If you drill large holes, 0.060", for the DIP IC, then you can use the standard machined socket pins that serves both as IC sockets as well as pins to plug into another socket. This is a 6502 carrier board plus RAM and 22V10. The 40-pin DIP for 6502 are 0.085" pads and 0.060" holes to accept machined socket pins up to their shoulder. The pins extended far enough to plug into a 6502 socket below and the socket above can accept a 6502.
Bill

Re: Thin pin headers for "piggy-back" boards

Posted: Wed Aug 14, 2024 4:54 am
by barnacle
A source for those pins, please, Bill?

Neil

Re: Thin pin headers for "piggy-back" boards

Posted: Wed Aug 14, 2024 5:22 am
by plasmo
I make full-size 4-pin oscillator sockets out of 14-pin machined sockets or 8-pin sockets for 1/2 size oscillator These are pins pushed out of machined sockets. Alternatively you can buy socket strip like this, https://www.ebay.com/itm/253662456287 and push out pins from the plastic holder.
Bill

Re: Thin pin headers for "piggy-back" boards

Posted: Wed Aug 14, 2024 6:13 am
by BigDumbDinosaur
plasmo wrote:
If you drill large holes, 0.060", for the DIP IC, then you can use the standard machined socket pins that serves both as IC sockets as well as pins to plug into another socket.

That’s basically the arrangement I used with my new SCSI host adapter.  In order to keep the pins square to the PCB, I mounted the PCB on the POC V1.3 unit and inserted the pins so they plugged into the receiving socket on V1.3’s board.  Then a touch of solder on each pin secured them.

Re: Thin pin headers for "piggy-back" boards

Posted: Wed Aug 14, 2024 7:50 am
by barnacle
Thanks Bill; that's pretty much what I've been doing. I was hoping you'd found a source of the pins alone :(

Neil

Re: Thin pin headers for "piggy-back" boards

Posted: Fri Aug 16, 2024 1:34 pm
by Osi
The disadvantage of machined socket pins are their dimensions
The pin can be 0.45 up to 0.55mm in diameter (see https://www.greenconn.com/en/ckfa103-a002.htm)

Compared to the PDIP terminal thickness of 0.25mm

https://www.ti.com/lit/ml/mpdi001b/mpdi ... me%253DDIP

Machined socket pins have the tendency to widen the sockets too much, so later, IC's will not make good contact again.

Re: Thin pin headers for "piggy-back" boards

Posted: Fri Aug 16, 2024 3:58 pm
by BigDumbDinosaur
Osi wrote:
The disadvantage of machined socket pins are their dimensions
The pin can be 0.45 up to 0.55mm in diameter (see https://www.greenconn.com/en/ckfa103-a002.htm)

Machined pins that are ~0.018 inches diameter are compatible with a regular socket.  Take a look at what Samtec offers for some examples.

stacker_pins_samtech.pdf
(179.54 KiB) Downloaded 34 times
socket_strip_samtec.pdf
(473.34 KiB) Downloaded 48 times

Re: Thin pin headers for "piggy-back" boards

Posted: Fri Aug 16, 2024 4:40 pm
by BigEd
We fairly often see damaged sockets in the land of Acorn, particularly because there are several projects which work by in-socket replacement of the CPU. One way to deal with a damaged socket is to put a turned-pin socket into it and then use that.

Re: Thin pin headers for "piggy-back" boards

Posted: Fri Aug 16, 2024 9:05 pm
by Osi
BigEd wrote:
We fairly often see damaged sockets in the land of Acorn, particularly because there are several projects which work by in-socket replacement of the CPU. One way to deal with a damaged socket is to put a turned-pin socket into it and then use that.
Yes, I've seen even projects using standard square pin headers of 0.64mm. Damaged sockets are 100% guaranteed.
I go with the thinnest socket header available, just for safety. And it also lifts up the piggy-back board a bit above any surrounding components like capacitors or other socketed IC’s