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

[whack]

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.

 

[betwixt]

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.

 

[whack]

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.

 

[KlausST]

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

 

[whack]

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

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

 

[betwixt]

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.

 

[whack]

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.

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.