Post by thread:[OT] 7 segment multiplexed digits

I ended up with a dual digit module of a 7 segment display from Digikey (part 67-1421-ND) and it's got multiplexed pins. Is there a general scheme for figuring out the data control lines on this or otherwise how can I learn to use it? I don't know the manufacturer off hand to look up spec sheets so I was wondering if someone offhand knew how to use multiplexed led displays. Right now I don't know what any of the pins do. Don't even know where the common connection is.

This is a COMMON CATODE (ground) green unit. LDD-C402NI from Lumex. Take a look at the pdf file: http://www.lumex.com/cgi-bin/pdf_filter.pl?1000132.PDF This unit is *not* multiplexed, to do it you need to connect same segment pins together, as pin 15 to 10, 13 to 12 and so on (see picture), exception to pins 4 and 5 that is the common catode pis, those two pins would be your "select digit" connected to two transistors to ground, and your pic would select which digit would lite. Common catode units are not the "best" to multiplex with a PIC, since the display will need "positive" level drive at the segments, while microcontrollers have the great ability to sink more current than drive it. Wagner. Lorick wrote: {Quote hidden}> > I ended up with a dual digit module of a 7 segment display from Digikey > (part 67-1421-ND) > and it's got multiplexed pins. > > Is there a general scheme for figuring out the data control lines on this or > otherwise how can I learn to use it? I don't know the manufacturer off hand > to look up spec sheets so I was wondering if someone offhand knew how to use > multiplexed led displays. > > Right now I don't know what any of the pins do. Don't even know where the > common connection is.

I have a similar problem.... 4 digit, 7 segment LDC display from Jameco (Item 17110). No data, no brand on it, no makings anywhere -- nothing but the pretty LCD display and it's 40 pins.... If you find anything, please let me know too. TIA Lorick wrote: {Quote hidden}> I ended up with a dual digit module of a 7 segment display from Digikey > (part 67-1421-ND) > and it's got multiplexed pins. > > Is there a general scheme for figuring out the data control lines on this or > otherwise how can I learn to use it? I don't know the manufacturer off hand > to look up spec sheets so I was wondering if someone offhand knew how to use > multiplexed led displays. > > Right now I don't know what any of the pins do. Don't even know where the > common connection is.