Quote:
Originally Posted by julie_m
The 74141 is just logic gates configured to energise one output depending which specific combination of inputs is presented. And logic gates are just switches, so it's not an insurmountable problem.
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Actually it is not just that at all. For a TTL IC the '141 is quite amazing, the off state voltage is rated at 60V.
There are plenty of other BCD to decimal TTL decoder IC's, but nothing like this one suited to Nixie tubes.
If you look on ebay you will find that the original TI ones are more difficult to get, but it turns out the Russians cloned them, and as a result plenty of equivalents available.
One interesting thing (and I have yet to meet anyone who knows about this particular example) is what happens when a BCD to 7 segment decimal decoder chip is sent illegal values that correspond to A-F, what they do with that. Some types produce blanks which is handy, others produce a giberish display, but......there is one type that does something really interesting and I could tell you how I found this out, but its too long a story, the IC is a 9374.
On passing it values outside the range of 0 to 9, on the 7 segment display it produces the output H. E. L. P.... not kidding, here is the data sheet :
http://pdf.datasheetcatalog.com/data...ild/DM9374.pdf
I was once greeted with this message on a multi-digit seven segment display under some interesting circumstances.