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4-bit 7-segment decoder with full hex output (more than BCD)

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whack

whack

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A very simple question here.

So there's the common chips like 4511 and 7447 which will do 4-bit BCD to 7-segment display... But, that leaves out the other 6 binary combinations, which we commonly represent as A-F.

Is there a single-chip 7-segment decoder that will display the full range of 4-bit values, 0-F?

Also, does anyone make an SMD version of 7447? I couldn't find one.

Help is appreciated.
 

Probably overkill but you could use a MAX7219 or MAX7221 which can drive any combination of segments across up to 8 digits from a single IC but they need a small amount of programming and use a serial interface rather than parallel BCD. They are available as SMD.

Brian.
 

That's a possibility. I also found variations of this sort of thing for fewer digits and less pins. Still, makes a simple thing more complex.

What I'm looking for used to be made, and even in SMD. But I will avoid creating a design that would rely on NOS chips.

This almost calls for a PIC, then again, it's shameful and sinful to do such a simple thing in such a complicated way.

- - - Updated - - -

For the PIC route this here solution is readily available:
http://jakeselectronics.net/projects_4bitbinaryto7segmenthexadecimaldecoder.php

Saves the time of having to write my own. Ready to use.

PIC16F628A of course comes in SOIC and SSOP package as well.
 

Hi,

Like the MC14495 or DM9368, or a complete disply TIL31? I think all are obsolete..

For sure you my program it in any simple PLD.

Klaus
 

KlausST said:
Like the MC14495 or DM9368, or a complete disply TIL31? I think all are obsolete..
Click to expand...

Basically sums up the problem. I don't think its a good solution to fish for NOS chips for a new design.
 

Note that several PICs are pin and 'almost' program compatible. The 628/628A may be more expensive than the 16F1826/1827/1847 which may be cheaper and are almost a drop in replacement.

Brian.
 

betwixt said:
Note that several PICs are pin and 'almost' program compatible. The 628/628A may be more expensive than the 16F1826/1827/1847 which may be cheaper and are almost a drop in replacement.

Brian.
Click to expand...

Oh, I agree. It's only a few cents difference so strictly from cost standpoint probably not worth changing, but I would adapt it to one of the 14-pin PICs from the 16F family if I wanted to spend time on that.
 

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