My Cable Extension

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This is just a breif overview of how I extended my FFC. Might be helpful for some out there.

My LCD is a Samsung 152T. Really nice desktop display - haven't played around with it too much in projection(only a couple vids and stuff) - but it looks good so far. In this monitor there is one 20 pin .5mm pitch FFC which requires extending.

Now I've gotten around to extending the flat flex cable and I've got a few pics.

First I ordered a bit of stuff from Digikey(all .5mm pitch stuff):
Some 20 and 30 pin suface mount(SMD) FFC sockets:
HFK20CT-ND
HFK30CT-ND
And some 6" Jump lengths of FFC:
HFF-20U-06-ND
HFF-30U-06-ND
An externally hosted image should be here but it was not working when we last tested it.


Using two of the SMDs I planned to solder or nickle print paint them in contact back to back. Like so:
An externally hosted image should be here but it was not working when we last tested it.

In the above picture the blue arrows indicate where the FFC would slide in, and the red boxes are the SMD contacts (I need to join the two red sets of 20 pins together). The two SMD's when put back to back as shown, but touching, should make an "extender" or a female/female 20 pin/0.5mm gender changer.

The actual 20pin SMD's up close:
An externally hosted image should be here but it was not working when we last tested it.

At first I tried to solder them together, but I couldn't find my soldering iron so I was trying to use one with a fairly large tip, and I couldn't get the solder to stay on one pin, it was flwoing all over the place (causing shorts). So I was like -:smash: - and decided - solder wasn't going to work out right now. So I decided to clamp the two SMDs back to back and apply some nickle print paint to each set of pins (this paint is conductive). So I cut out a couple peice of acrylic and got some nuts and bolts and made a little clamp - really simple, could be done with wood and possibly even metal (just watch out it doesn't short and connections).

Before I got to the nickle print however I decided to test if the back to back clamping was causing sufficient contact, to my suprise all 20 connections had a low resistance (meaning they were in electrical contact). I deicided to plug it in and see if it would work with the lcd.

And it did!
An externally hosted image should be here but it was not working when we last tested it.


So it's a solderless, fairly easy cable extension. Unfortunately the SMD's and jump cable isn't real cheap through digikey the 2 SMDs and 1 6"(the longest they stock) jump length cost about $10CAD + shipping, handling and time - it can be kinda expensive if you need more than 6" extension. Its not a lot of money but keep it in mind when comparing the cost of 2 LCDs.

One problem I had was getting the cable to stay in the SMDs, the way the clamps work on these particular SMDs is a flip rotary clamp, and its kinda tricky to get both in the clamps when they're so close together.

Is it loose? Nope. It doesn't flicker when I jiggle it, and those little SMDs aint going anywhere. After I got it clamped in I cranked down the screws/nuts andmade sure it was conductive and functional.

Since the picture of the assembly I've cut down the acrylic a bit and the screws a lot - the less weight in the assembly the better. But it's really not that heavy - and the rotary clamp on the SMD sufficiently holds the assembly in mid air.

Any Q's or comments welcome.
 
WOO HOO this does indeed work,but what I did was VERY VERY VERY carefully epoxy the two connectors together instead of clamping them together.

Just one thing,if you go with the epoxy,apply it with something VERY small,like a q-tip or something similar.And make sure you dont get epoxy on the metal contacts.
 
The two cables pictured above are both under 1" wide, at .5mm pitch the 20 connector cable (not in bag in pictures) is about 1/2" and the 30 connector cable is about 3/4" (in the bag in the pictures above).

The part numbers I listed:
HFF-20U-06-ND
HFF-30U-06-ND

Are digikey part numbers you should be able to find them in the catalogue or on the website.

If you're uncertain of what cable your panel uses, I foudn the easiest way to find the pitch and connector count, is to scan the cable or connector on the lcd at high resolution, and count or measure it.

Hope that helps
 
It was the 20 Pin(30 pin was for a different LCD); however, as this article is quite old, my own methods of extension have changed and simplified. Trust me when I say this is good news. I don't have the details on part numbers right now, but I can check at home this evening - I caneven remember if I got the new parts at digikey or some other supplied.

But the jist of the new cable extension is using one vertical mount SMD and squishing two FFCs into the one slot, contacts facing each other, and lock the SMD connector in the closed position.
 
It's also possible (with a little care) to insert two cables into one surface mount socket, assuming the pins on the cable are facing each other then you get a nice easy extension, and once the socket is clipped down it's extremely firm. If you buy an extension cable with the pins on the same side then you don't even have to worry about inverting the order.

I've used this method a few times and it works like a charm, the hardest part by far is getting both cables into one socket, it just takes a little patience!
 
I'm having a bit of trouble getting the FFC extension in place. I got the 6" FFC extension and the SMD FFC connector, but I can't seem to clamp down on the FFC extension with the existing (on PCB) connector - as if the FFC is too thick or something. It goes in, but when I close the little latch, one side of it (the latch) pops out of its socket. The FFC will stay in the socket, but I'm hesitant to just leave it hanging like that. Thoughts?

Also, Mr. Kh, how did you get the cable extension out of the way of the LCD? 6" doesn't seem like enough and your picture makes it look like the FFC would still block like from the LCD. Can I get another FFC and make a 12" extension?
 
Take the black plastic stuff off of the FFC, especially if you're putting two in one SMD. I found the Black plastic backing can be helpful if it's loose, but if its fine without the extra thickness it's better without.


To get the cable out of the way, don't do it like the picutre, fold out BOTH PCBs and runn the FFC kinda like out toward the camera (in my pic) and down under. once you have the route properly decided making harder folds in the FFC will help keep it in place without too much 'residual stress'

I hope that makes sense - I haven't had the 152T for like... Over a year or so, can't rememebr everything but I did get the cables routed, and I'm pretty sure I took that black backing on the FFC off to fit in the LCD SMD.
 
In UK need some help/assistance pls

I am trying to get the same kind of connectors, but kinda new to this solder/clamp thing, do you have any close ups of how the connecters were pushed together PLEASE

Is the following >>>Flat Flex Cable Connectors<<
http://www.imperial-connect.com/products/05easy.asp
The same as HFK20CT-ND

ALSO WHEN CHOOSING THE >>>Flat Flex Cable<< what is similar alternative to the mentioed HFF-20U-06-ND

BELOW IS A MADE TO ORDER CABLE LINK, CAN SOME1 HELP ME CHOOSE
http://www.imperial-connect.com/products/ffc/FFC_info.asp

There are so many different type its hard to pin point them.

Thanks

Eilz
 
Yes those are the ones, RS also sell them if you can't find the correct size, however you need to buy a minimum of 10 cables and 10 sockets from them I believe.

All extensions I've seen have been for 0.5mm pitch FFC cables, if you clamp two cables in one socket then you want to get a Type A cable.
 
With a bit of luck this link will work: Link

If not you can navigate through:
Electronic Components, Power & Connectors > Connectors > Multipole PCB > Interconnections Systems - Signal > 0.5mm FFC

or try stock numbers 459-1976 (20 way cable) and 332-3277 (20 way straight entry connector).

Any of the above should put you on a page with all items listed so that you can choose the one you need.

You can probably get them much cheaper than off RS by looking around but for a couple of quid I personally didn't think it was worth the effort!

Steve
 
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