A technogeek anniversary to celebrate

WARNING: Extreme electronics hobbyist geek content 

I recently found out, due to a couple of videos showing up on YouTube that it's the 55th anniversary of an analog integrated circuit that was instrumental in pushing analog integrated circuits into more and more products. Originally designed at Signetics corporation, it's the 555 timer circuit, AKA "the triple nickel" timer. Ironically, the triple nickel has outlived Signetics itself, which was bought by Philips Semiconductor in 1975 and Philips is now part of NXP semiconductors. 

The first video I watched, from the EEVBlog , talked about the 555 timer design effort being led by Hans Camenzind (1934 - 2012) in 1971, and that it has been a remarkably successful product. As seen in many other times and places, the right concept at the right time becomes a standard approach to many things. The first time I ever used one is hard to recall exactly, but I remember it being in the late 1970s, and like most people, once I've successfully used one it tends to be the one I think of when I need a part like this. Yes, there's all manner of planes, civilian and military with triple nickel timers in them and only a few were designed in by me. 

That EEVBlog video is a good overview, but a better technical overview of using the part is at Build-Electronic-Circuits (.com!) They provide this illustration as a simplified equivalent circuit, pretty much a good description of the part. BTW, there's probably no connection between the three 5k resistors in series at the top (5k 5k 5k) and the part's name. Probably. That's what the experts say.

When I decided to post about this, I didn't really intend to get into how to design circuits that use this chip. There are many different things that this chip can be used for, and that Build-Electronics-Circuits page shows many - something with that much deep coverage wouldn't be a good fit for this blog. A second video talks a bit more about various things that it can do with more details. 

The 55th anniversary year of the 555 is unusual and part of that has got to be that it's an analog part and not a microprocessor. The closest equivalent microprocessor from 55 years ago would be the Intel 4004 -the first CPU ever sold as a standalone product - and only a four bit processor. I can't tell you the last time I saw a 4004, but I think it was in radio being repaired 30 years ago. The radio was obsolete and no longer in production, but it was customer's return and the warranty is honored as long as possible. 

I figure there's a chance that some of you will have worked with the 555 and remember it fondly.