How to connect a 7-Segment display?

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Lac

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Am I able to connect a BCD to 7-segment decoder with active-LOW outputs (7447) to a Common-Cathode 7-segment display? I assume I'm not able to do that, but is there a way to convert the BCD decoder chip's output, so I'm be able to run the Common-Cathode 7-segment display at that chip? I mean, are there a way to make the output signal of the 7447 to be HIGH instead of LOW`?

The reason for this is that i have bought the wrong chips for my 7-segment displays.

Cheers!
Lac.
 
I had the same problem once. You could try placing a string of NOT gates in between the inputs. Phillips builds a 74F756 octal inverter-buffer (with open-collectors) that should work well enough. Other octal inverters are available for other logic families too, of course. It might just be easier to order a 7448, or a common-anode display.
 
After a lot of searches, I found out that the 7448 is obslette! And i don't want to spend a lot of money buying new 7-segments! The solution with NOT chip uses awfully lot of space! I have got like 32 7-segments and each of them have got 7 inputs, that's 224 lines that I have to connect a NOT gate to, and each chip conatains 6 NOT gates. That means that I need 38 NOT chips!!! That will use up WAY to much space!

Any other solution? Aren't there any substitute for the 7448 since it obslette?

Cheers!
Lac.
 
 
Thanks!! I found those chips here in Norway too, and they were pretty cheap (half a dollar - 4,74 NOK)! Thanks again! Now I just hope these chips will work

BTW. what is Vss and Vdd? I assume Vss is +5V and Vdd is ground? Am I right?

Cheers!
Lac.
 
Lac said:
BTW. what is Vss and Vdd? I assume Vss is +5V and Vdd is ground? Am I right?
Click to expand...

You've got them backwards - Vss=ground, Vdd=+5v.
Sounds like those chips should work well for your application ...
 
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