FotS

The 7490 is OLD… as the hills! It has been around since the 74xx (and the Mil-Spec 54xx) series logic appeared back in the 1970's. It is an obsolete part, largely superseded by specific counters but it has to be one of the most versatile counter/divider chips around - and you can still get hold of it, pools of old new stock exist.

It has been the recipient of most of the new technology updates and you can get them in tiny packages with speed and power foot-prints to match.

I don't know where it originally came from but I have had this graphic in my collection for years (thanks Sam, whoever you are) and it shows all the common methods of connection for making this one chip divide/count anything from 2 up to 10. 

Let's hear it for the 7490. What a useful chip.