[chuck richards]

Was just checking http://www.bgmicro.com yesterday looking for a
few various ics.

Came across this interesting one they currently have for sale
on their "Virtual Sidewalk Sale" portion of their website:

It's the old National Semiconductor DS8880 high-voltage
7-segment decoder/driver ic. It's a 16 pin DIP and they are selling
them for $1 each. Got the data sheet. It says it can drive a
gas-filled
7-segment readout by pulling the appropriate segment cathodes low.

It does the full hexadecimal decoding.

It has programmable current sinks on the 7 outputs.
Programmable via an external resistance on a single pin.
It can stand up to 80 volts on the outputs an it'll do 1.5 mA
max current.

The application diagram shows a typical circuit which looks just
the same as a regular "1-of-10" nixie tube connected to a 74141.

This DS8880 ic looks to be the 7-segment equivalent of a 74141.

The app. note suggests a Beckman 7 segment tube.

Have any of you guys ever messed around with those?
Looks like possibly an interesting find for $1 each.

I do not have any gas filled 7 segment tubes at this time.
But maybe now that these driver ics have become available, it might
be time to find some!

What are your thoughts on this?

Thanks, Chuck


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[gregebert]

I recall a similar device from Burroughs/Sperry, the DD700. It had BCD inputs and drove the segments. I found a pinout for an Ebay listing, and the DD700 also has programmable drive-strength. Perhaps a competitor device to the DS8880 ?

Certainly work trying. Even a $10 Raspberry Pi has enough GPIO pins to drive several digits