Help shrink the prop chip

Humanoido

The prop dip has a defined width/distance between pin rows.
Is there a socket adapter with pin rows closer together?
Space is at a premium on this pcb.

humanoido

Leon

Use a QFN chip.

Leon

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Amateur radio callsign: G1HSM

Graham Stabler

You can put components underneath the the DIP propeller, I've seen several people put the eeprom and crystal under there.

But I've not seen an adapter, I would tend to go towards a soldered solution (though perhaps not QFN) if you really need more space. Be positive, you won't blow up the chip!

Graham

Humanoido

Leon: Its a series of DIP chips with pins that I can see and
work with.

Graham Stabler: what soldered solution are you talking about?

Components can mount under the chip but what
I want to put there are more prop chips. Shrinking the socket
on the bottom but not the top is one idea to gain real estate.
The dimensions of the prop chip is not important as the second
prop can mount on the pcb back side.

It's possible to manually bend pins inward, but that's going to
take a long time and require lots of skill to get the pins to line
up in new rows, and so this method is not so practical.

Phil Pilgrim (PhiPi)

Maybe you want something like this?

····www.arieselec.com/Web_Data_Sheets/12030/12030.htm

I don't see what it buys you, though, since it precludes putting parts under the Prop chip. If you really want to save space, do as others have suggested and use one of the SMT parts.

-Phil

Humanoido

Thanks Phil! This is exactly what I was looking for.

Martin Hodge

I wonder how many props you could wrap width-wise around a "cylindrical" backplane using some of those wide-to-narrow adapters.

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Martin Hodge
"I like Pie"

Tubular

Shmoopy said...
I wonder how many props you could wrap width-wise around a "cylindrical" backplane using some of those wide-to-narrow adapters.

Now you're talking.· Offset each "row" by half a prop and you've got a prop double helix (DNA like).·· The two helixes would actually be Gnd and 3v3 however

·

Graham Stabler

You could make the same adapter with a bit of veroboard and some header pins if you are stuck.

But I *may* have a better solution, I did try to write an explanation but I thought I would just try it, however I don't have any Dip propellers or sockets so I made a miniature version. You will end up with a sort of blade with just the propeller on it (and eeprom and crystal if you want).

Step 1, make a small board with your socket soldered in place. Break the tracks between the two sides of the socket. Add some headers on one side to make an edge connector. Add the same headers this time through the holes but put the long legs of the headers through the holes. The second set of headers are used to join the two boards conveniently.

Step 2, make a second board and solder on another "edge connector".

Step 3, solder the two boards together.

You now have a propeller socket that can plug into a board and take up little space particularly if set back to back. It is worth cutting the legs of the socket down after soldering just because of the small chance it might contact with the second board.

With a double sided PCB it would be even easier using the double row header pins as an edge connector.

Cheers,

Graham

p.s. Apologies to the vero-board for my messy cutting (done with a knife)

mctrivia

i know you like dip because you can solder. but if you want to make a lot of props on a board I will make you a great deal.


I will design and assemble a custom pcb with a lot of qfp props on it for a very low price. The more props you want the cheaper/prop it will get.

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24 bit LCD Breakout Board now in. $24.99 has backlight driver and touch sensitive decoder.

If you have not already. Add yourself to the prophead map

Mike Huselton

Also, think three-dimensional stacking with increasingly wider offsets between layers.

Mctrivia, as I recall, you prefer BGA. Correct?

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JMH

Post Edited (Mike Huselton) : 2/19/2010 3:56:18 AM GMT

Graham Stabler

My guess is the ability to reconfigure may be important in super computer experimentation.

If the mini-blade type idea seems suitable a version based on a QFP/QFN would be very compact and thin allowing really good packing density. A proper high density edge connector might also be used reducing the size further.

Graham

Humanoido

Graham Stabler said...
You could make the same adapter with a bit of veroboard and some header pins if you are stuck.

Graham: this is remarkable. Thanks for showing how you are able to create this remarkable socket. Look at the tight distance you were able to achieve between the mounting pins - it's very suitable for creating more compact arrays in hypercomputers. Thanks for sharing the photos.

humanoido

Humanoido

Mike Huselton said...
Also, think three-dimensional stacking with increasingly wider offsets between layers.

Exactly! I was just in the process of making a stack when I read your post. What I'm curious about are the pins that contact pins and how they can be used in a 2 or 3 chip stack. The Propalyzer has this configuration with a few pins bent up to take the programming. So exactly how can these processors be accessed and programmed if they share all their pins?

humanoido

Graham Stabler

Glad to be of help.

Graham