Sourcing replacement flat flex connector - Page 1
Forum section: electronics / projects

author: papo
author_rank: Regular Contributor
timestamp: July 29, 2013, 02:53:04 pm
content: Hello everyoneIn an attempt to clean out the dust from a HP dv6 pavillion laptop, I broke the plastic lever of the connector fastening the keyboard flat flex. One of the two plastic hinges broke off (top left corner in the picture):I tried to tape down the flat flex but that did not work. I am now trying to resolve this situation by either one of the following strategies:Sourcing the exact same connector and replacing the broken lever.Sourcing a connector with the same footprint and replacing it.Not touching the connector that is already soldered in, sourcing a connector that fits the flat flex, solder it to a custom PCB and solder wires from the PCB to the pads of the existing connector.Soldering a non-flat flex connector (most likely using wires) to the flat flex and soldering wires from the pads to a mating connector.I also considered soldering wires directly from the flat flex to the pads but I'd rather not do that because these wires could easily be ripped off.I tried 1. but I can't find the connector. As for 2. and 3., I don't seem to be able to find a matching connector. The flat flex has 32 contacts with a pitch of 1 mm. I usually order my stuff from digikey or RS; digikey has a few of these connectors but all of them are out of stock, and RS does not have anything in that respect. I managed to find some distributors which have presumably matching connectors, but I'd rather not play > $30 shipping for a $1 connector. Does any one know about any other option I have regarding 2. and 3.?Also, I'm not an expert on flat flex cables, but the one that comes with the keyboard has a thickness of roughly 0.3mm, measured including the blue plastic strip:I noted that the contacts are coated(?) with a black material which could be carbon on the other side:I am now wondering whether a connector designed for 0.3 mm thick flat flex would fit that. Doing some research, I found that there is a family of flat flex called CIC which require special connector. These cables are apparently manufactured with conductive ink. I am not sure whether I need a FFC or a CIC connector, given that the black substance could be ink...Also the cable has little wings as you can see in the picture above. These wings are used to retain the cable when you push down the lever. I was not able to find "lever-type" flat flex connectors for 1 mm pitch and 32 contacts at all. Hence I am wondering whether I can cut away these wings and get away with the "retainer clip" type of connectors. Or in general, what do I have to consider in addition to contact number and pitch and cable thickness?Lastly, I would like to know whether it is possible to scrape off that black coating to get access to the contacts for soldering as described in 4.Also, I'd welcome any general hints on the topic. Here is a picture of the existing connector with the pads where I would solder the wires in 3. and 4. Please excuse the blurry picture.Regards and thank youMatt

author: G7PSK
author_rank: Super Contributor
timestamp: July 29, 2013, 05:22:25 pm
content: I have solved that problem in the past by inserting the flat flex into its slot and then inserting a piece of thin plastic over the top of the cable thus holding down the flat flex. I know this is a bodge but it does get you out of a jam.

author: papo
author_rank: Regular Contributor
timestamp: July 29, 2013, 05:52:37 pm
content: HelloThanks for your reply. I believe that this can be done with the types of flat flex connectors where you have to insert the cable and then plug in some sort of fastening brace. The connector in question however has a lever that presses down the cable. The black lever forms the slot together with the white base, but if the lever is missing there is no slot there in the first place. (Or am I missing something?)Regards and thanksMatt

author: wraper
author_rank: Unknown
timestamp: July 29, 2013, 08:31:32 pm
content: Hi, for me it seems that you can still use that lever. I had the same problem couple of times. Usually someone broke it before notebook arrived to me, one of them was dv6-3000. All you need is to insert that lever back in the way that all metal pins are inserted into the corresponding holes in the lever, insert flex in a way that lever is still on its place. Close it and put a piece of tape on it, so it won't open and fall accidentally. Done.

author: papo
author_rank: Regular Contributor
timestamp: July 29, 2013, 10:55:54 pm
content: That's exactly what I tried but it looks as if the tape would not apply a sufficient amount of pressure to the cable. Only parts of the keyboard work when using the tape approach. If I press down the cable with my finger, the amount of working keys varies with the pressure I am applying. I guess that I need something stronger than just a tape if I were to use the original connector. Thanks anyway.

author: wraper
author_rank: Unknown
timestamp: July 30, 2013, 12:28:57 am
content: Well, plastic hinges on the side are only to hold lever in place when connector is open. When it's closes it should hold in place even without them. Tape is only a measure for extra confidence, should be OK without any tape or pressure on the connector. On photo that lever seems OK except broken hinge. What I suspect is that some of metal pins are bended on connector itself. Or you just didn't place that lever back correctly. As I said when is's closed it should be exactly the same with hinges on side or without them. Pressure is produced locally on each metal pin individually by lifting each of them with that plastic rectangle with hole. If those rectangles are not broken then either metal pins are bended or the whole connector is deformed (middle pops upwards). This type of connector is not working like lever pushes flex against pins. It actually lifts pins on one side so other side of pins is pushed against flex.

author: amyk
author_rank: Super Contributor
timestamp: July 30, 2013, 07:05:27 am
content: Quanta make the dv6 but apparently they don't put part# for connectors on their schematics, which is where I first looked.I see some writing on the connector but can't read it exactly; what does it say? On the right is what looks like "65B4" but that seems more like a datecode to me, the left is unclear.

author: Grayfox
author_rank: Regular Contributor
timestamp: July 30, 2013, 02:25:50 pm
content: I damaged the tabs that hold my Asus U36SD mouse cable in.So i used strong tape to keep it inside the connector.Does the job.