Need a 7 seg display driver with hex capability

[ljcox]

Does anyone know if there is a 7 segment display driver available that can output hexadecimal digits, ie. 0 ~ F?

I can only find them with 0 ~ 9.

Any advice will be appreciated.

 

[Pommie]

It would probably be easier to use a pic. Ambient recently posted this thread.

There was also a recent thread that used a 16F628 to do the same thing. I.E. take two 4 bit numbers and display them on a dual hex display.

Mike.

 

[blueroomelectronics]

If you're lucky you might be able to score a handful of TIL311 displays off eBay.
**broken link removed**

 

[Torben]

All the ones I can find so far seem to be either out of production or maybe overkill. I think the **broken link removed** can do what you want (but I've only take a quick look at the datasheet)--but if you need only one digit, the 40-pin count and ~$6/unit price (at DigiKey) might be a problem. Maybe a sample?


Torben

 

[ljcox]

It would probably be easier to use a pic. Ambient recently posted this thread.

There was also a recent thread that used a 16F628 to do the same thing. I.E. take two 4 bit numbers and display them on a dual hex display.

Mike.

Thanks Mike, a PIC would make it very easy. But, the person I'm helping lives far away and has very limited electronics knowledge.

So I doubt if he would want to use a PIC given the learning curve and the need for a programmer etc.

 

[ljcox]

All the ones I can find so far seem to be either out of production or maybe overkill. I think the **broken link removed** can do what you want (but I've only take a quick look at the datasheet)--but if you need only one digit, the 40-pin count and ~$6/unit price (at DigiKey) might be a problem. Maybe a sample?


Torben

Thanks Torben, I'll have a look at the DS.

 

[on1aag]

Hi Len,

Avago still has some but actually getting them might be an entirely
different ballgame.

**broken link removed**

on1aag.

 

[Papabravo]

Max6954

Icm7218

 

[Mike - K8LH]

Would something like this work? It outputs '0' through '9', 'A', 'b', 'C', 'd', 'E', and 'F' characters.

This is pretty much a finished PIC project (except I think we might have added a pull-down resistor on the base of the 2nd transistor). The code is posted further down in the first page of the following thread;

dual 7-segment display controller

Regards, Mike

 

[Dean Huster]

There are 2 or 3 CMOS D/Ds that output hex. The older 9368 was another wonderful one and used constant current outputs so that you didn't need current limiting resistors. The TIL311, even back when they were more easily available, would usually set you back about $10 or more EACH!

Dean

 

[Hero999]

Why not use good old fashioned CMOS combinational logic?

It's pretty much your only solution if you don't want to program anything or spend loads of money on a specialised display.

EDIT:
What about the DM9368 or the MC14495?

 

[blueroomelectronics]

There you go, like Hero999 said the MC14495 should be perfect.

 

[Mike - K8LH]

Is there another part number? Just tried searching for MC14495 on Jameco, Digikey, and Mouser and none of them turned up a product match.

 

[blueroomelectronics]

Probably been discontinued for years. Seems some TTL & CMOS chips are becoming harder to find.

That said, your 16F628A solution is probably cheaper too.

 

[ljcox]

Thanks for the responses.

A PIC solution would be perfect if I was doing it myself. The whole system could be done by a PIC with a few sundry components around it.

But the op I'm helping has very limited electronics knowledge and no PIC knowledge. So the learning curve for him would be very steep.

At the moment, I have suggested a decimal (BCD) solution in lieu of the hex one.

He initially rejected the BCD one but I think his reasoning is flawed.

 

[Mike - K8LH]

Sorry. I suggested the PIC project as it's pretty much complete and thought perhaps some kind soul near the OPs location might be able to 'burn' him a one-off '628A to send to him.

Mike

 

[Hero999]

Is there another part number? Just tried searching for MC14495 on Jameco, Digikey, and Mouser and none of them turned up a product match.

Did you try searching for CD4495?

There might even be an HC/LS version of the TTL version.

Failing that, you could use a CMOS BCD decoder with some additional logic to make a hex decoder.

 

[Mike - K8LH]

No I didn't. I'm not familiar with this particular component and I was simply interested in looking at the data sheet. I would have no way of knowing that a CD4495 is the same device, which by the way doesn't show up in a part number search on Mouser either...

 

[Hero999]

http://www.ortodoxism.ro/datasheets/motorola/MC14495P1.pdf

As far as suppliers are concerned, I Googled for a couple of miniutes and this is what I've found:
**broken link removed**
http://www.1sourcecomponents.com/partinfo/mc14495.htm
http://www.huskyintl.com/partlist/part_details/MC14495.htm

 

[blueroomelectronics]

Just a note on the 16F628A version. The PICs have about 65ohms resistance on when driving an output pin. You could skip the resistors as the displays would only get about 29ma per segment (assuming Red displays), plus you're muxing them so they should be just fine, bright too.