SparkFun Forums

[Zurgy]

I'm looking for a connector for a membrane keypad* which terminates in a flexible ribbon cable. SparkFun have something along the lines here:

http://www.sparkfun.com/products/8973

However it's designed for an SMD board with 0.1mm spacing, I'd like something suitable for a breadboard.

Can anyone tell me what this type of connector is called so I can go searching for other examples?

Thanks,

Ben.

* the one on the new BigTrak toy.

[colinb]

What you need is an FFC (flexible flat cable) / FPC (flexible printed circuit) connector. The SparkFun receptacle you mention is similar to all the FFC/FPC receptacles I've seen. Some are simply friction-retention and some have a lever that you press after inserting the FFC/FPC. Here's another example of a common FFC/FPC receptacle.

I've never seen an FFC/FPC connector that have 0.1" pin pitch since it's a huge difference from the native cable pitch. What you will probably need to do is make a breakout board. I've done this for some LCDs and it's not hard if you've made PCBs before. It would be a fairly difficult PCB to fabricate at home (e.g., toner-transfer, etc.), but for a few dollars you could get three boards made at Laen's DorkbotPDX PCB order and have them in a couple of weeks.

An alternative if you want it quick and dirty is to super-glue the FFC/FPC connector down on some perfboard (make sure pins are insulated from the board by using the back side or some Kapton tape). Then use 30-32 gauge UEW (aka magnet wire) like ChaN uses or some 30-gauge wire-wrap wire, a fine soldering iron tip, and lots of patience to break out each FFC/FPC connector pin to a 0.1" pin header on the perfboard.

[Zurgy]

Thanks ColinB.

Information is really useful, I can see there's a huge range of connectors about but most of them will need a breakout of some description. The quick'n'dirty technique looks interesting in a masochistic kind of way, especially for wiring SMD ICs!

Quite happy to design a board. The BigTrak, being a toy, has some interesting cost-cutting measures. It doesn't use a connector at all, just pads on the PCB with a piece of plastic holding the cable against them. I might adopt the same approach as I can reuse the piece of plastic and screws with my own board. Sorry, no photo as I'm parted from it at the moment.

Was thinking of making a BigTrak shield for the Arduino with an H-bridge chip on it and XeeBee interface. Just had some very decent boards made by Olimex in Bulgaria. Might give Dorkbot PDX a go as they're much cheaper for smaller circuits and he's only charging $5 for international shipping.

Thanks again,

Ben.

[Tommy Tween]

This website has a Bigtrak Shield - http://iskudo.com/products.html