Big 7 seg LED display

[keithdoxey]

Thanks for your replies everyone..
Is there any logic level convertion IC that can do this???

If i feed the output of the pic to a 4011 (AND gate with its both inputs made 1 common),
and then give it to a PNP transistor, will it work???
I think the AND gate will do the level conversion, i'm not sure ? ! ?

No. The 4011 will still be connected to the 5v supply so the PNP will always be driven as its base will not be allowed to go to 9.6v to turn off.

You could use a chip with open collector or open drain outputs. Another ULN2803 would do the trick but would occupy about the same space as the three resistors and NPN transistors it replaced.

[sayzer]

shahidali55,

As Keith said, you will most likey have to use two ULN type of drivers.

Thats seems to be the way.

Also, why not consider mat's schematic?

Or if you have limitations, why not try finding Big Led displays with 5V, if there is any?

[shahidali55]

Big displays of 5v are not available...
Thanks for the schematic Mat.
Will your circuit work for 12v displays also???

[shahidali55]

Will this work ? ? ?

[mat janssen]

Will also work on 12 volt, 15 volt.
I cannot open your schema. There is something wrong with the server I think. Because I could also not upload my diagram's like that, so I post them somewhere else, and gave a link to this forum.

[Dave]

shahidali55, Why not just use a UDN2981 for the sourcing driver as it is a direct connect to the PIC?

Dave Purola,
N8NTA

[keithdoxey]

Why not just use a UDN2981 for the sourcing driver as it is a direct connect to the PIC?

Excellent find Dave. Have downloaded the datasheet and will almost certainly be using this chip in the future.