SparkFun Forums 

Where electronics enthusiasts find answers.

Have questions about a SparkFun product or board? This is the place to be.
By SnarkyFish
#16403
So i'm working on a project similar to this one:
http://www.readymademag.com/feature_24_stereolab.php

i've got a more or less functional really old laptop where most of the plastics are shot, (and have been replaced twice.)

If you read that article, the guy really glosses over the complexity of extending the lcd control cables to 2 feet.. it's kindof a massive undertaking, as we're really talking about some super thin 40 conductor ribbon cable thats less than an inch wide.

What i'd like to do, is just build an extension cord compatible with those connectors...

So, heres the connector data i've collected. 40 pins, 1/2 inch by 3/16ths inch.

it looks like this:
Image

I'm basically praying that these are a standard connection and someone can help me identify them. At that point, i'd like to make or buy a spark fun style 'breakout board' that would get those connectors up to a size that i could solder my own 40 pin extension cable.

Does anyone have any info on these?
By Roko
#16406
The look kind of like Hirose board to boad connectors;

http://www.hirose-connectors.com/connec ... ectors.htm

They list a bunch of their board-to-board connectors there.. Your best bet would be to measure the pitch (Might be best to try measuring it in both metric and imperial... And look for the more "round" number first), then check the datasheets from Hirose for board-to-board connectors for that pitch to ensure all the other dimensions line up.

Looks similar to their 0.5mm connectors to me, as the dimensions line up closely to what you posted, but without more accurate measurements, it's tough to say.

http://www.hirose.co.jp/cataloge_hp/e53700036.pdf

Check out their other datasheets on the first link to see if you can find one that matches the mechanical shape more closley.

Hope that helps.
By silic0re
#16408
i haven't seen anyone do this is in a while :)

a long while ago when 386's still roamed the earth in plentiful numbers i heard that a friend of a friend had taken four laptop panels out, hung them on his wall, and run cables from them down to this XT with many video cards. He used the panels to run different screen savers, and apparently it looked really cool (though I never got to see it).

Sometime later I made my own version of this -- just with a single screen, mind you. I used the laptop guts from an old laptop and just hung it on the wall, with the board off away elsewhere.

In any case, the point of my nastalga is to give you a hint on why he may have neglected to include information about the non-trivial task of extending one of those flat plastic cables: some laptops actually use a large number of wires instead of a flat cable. That way one can clip an individual wire, solder in an extension, and move to the next wire (as he describes doing).

If you do decide to take the make-your-own-cable route (as opposed to the extension procedure he describes, which I'm not sure is possible with those flat plastic cables), then you could see if there is a Schmartboard that you could use as a breakout board for the connectors. It's like a generic breakout board for surface mount components.

http://www.schmartboard.com/

hope that helps!
silic0re
By SnarkyFish
#16414
Thanks Roko! atleast that gives me a name and some specs for what i want. The DF18 and the DF23 look pretty close to the mark. i just need to compare measurements.

Any idea how i can come up with a place that sells these things in lots less than thousands?

silicore.. thanks! yeah.. it hadn't occurred to me that the footprint on these things would be pretty much the same as any surface mount IC with 40 pins.. that gives me hope for not having to design something for a project i thought would be quick and dirty.

yeah.. alas.. this inspiron from about 8 years ago has a very thin.. non modifiable cable..

also, unlike the screens on those old 386's, you can't really talk to a laptop lcd with just any old vga out anymore, as the hardware is usually all pretty proprietary and integrated with the machine. Still, if i can pull off a lengthy cable run.. (i don't know that either) it should make for a pretty good livingroom mp3/photo viewer appliance.
By SnarkyFish
#16698
Thanks! that might be the closest match yet!
By SnarkyFish
#16702
sorry for the noobish questions, but does anybody have an online source for small quantities of these things? I've tried digikey, but i've had no luck.
By SnarkyFish
#16704
Scratch that, i found someone. (http://www.mouser.com)
Once i resolved my exact part to a molex part number finding someone to sell it was just a google away.

So, I've ordered those, i'm crossing my fingers that they match up. My next step would be to find a 40 pin breakout board to mount them on. It needs to be relatively small, but big enough that i can through hole solder the connections for these buggers.

I have specific product data on both connectors:
http://www.molex.com/cgi-bin/bv/molex/j ... Lang=en-US
http://www.molex.com/cgi-bin/bv/molex/j ... Lang=en-US

hey sparkfun, if i can come up with a suitable board for these things, what would you charge to reflow them for me? (so i don't have to go shopping for griddle hacks and whatnot) Your office is about 15 miles from my house.
By reklipz
#16711
SnarkyFish wrote:Your office is about 15 miles from my house.
Aren't you a lucky dog.

That would be sweet to see SFE in action. I think you need more pics of the office on the website to be honest.
By SnarkyFish
#16716
yeah, if you're local you can just pick your stuff up. (they're not the easiest to find) The place looks like a few guys in a room full of gear to me, but man.. i want to be their best friend.

maybe next time i hafta pick something up i'll bring beer, that might grease the wheels for reflowing some boards for these things.. ; )
By SnarkyFish
#17285
Ok, so i've got the connectors, my next problem is putting them on 'breakout' boards of sorts. The pins have a .5 mm pitch, which, to my unexperienced eye, is practically microscopic.

The earlier suggestion of using a Shmartboard will work for one of the connectors (the one that connects to the screen hardware) but it won't fit down inside the laptop for the other connector. That connector needs to sit in an 33mm x 18.5mm (w/h) space. (that's 1.2 inches by .7 inches, to you non metric folk)

for a visual example, check out the bottom picture above.

Do i have to make a custom board? how would i go about doing that?


any help, as always.. is greatly appreciated.