Comment by jwr
16 hours ago
The 555 timer is still the most popular chip that hobbyists add to their parts inventory (see rankings at https://partsbox.com/ecdb.html). I find this both interesting and curious — I'd say it has mostly nostalgic value at this point. Almost every practical problem today is better solved by something else. And yet it persists, I guess mostly because of beginner tutorials and first LED blinky circuits.
One nice thing about the 555 is that at least it aged well and still is very usable in those beginner tutorials. Unlike for example the uA741 which no one should use.
> Almost every practical problem today is better solved by something else.
I'm curious about this claim. It's certainly easier to just wire up a modern microcontroller, but is there a better option that involves no software and is likely to still work the same today as it did 50 years ago?
Why is no software so important? If you design your board well enough, you can route the programming ports somewhere you can program it in-situ, possible with other components that also need programming.
But in terms of cost, a simple microcontroller is usually cheaper than a 555 nowadays, often doesn't require external components, and so even if all you wanted was a single function like an edge-triggered pulse, or generate a single frequency, it probably still makes sense to use a microcontroller from a board design perspective. As soon as you want anything slightly more complicated, odds are you can replace a ton of other circuitry on the board with that single chip and a small program.
While it incurs a programming issue, the microcontroller will generally be more stable, less temperature sensitive, and consume less power.
For other posters saying 'just wire up a microcontroller': please self-reflect on your disregard for the concepts of simplicity & elegance. Never mind robustness, or educational aspects.
'Grab laptop, fire up IDE & plug in programmer cable' vs. 'configure the circuit using a soldering iron'. Both have their place.
I find it much easier to write a ten line program for an 8 pin CH32V003 (or ATTiny85 in past times) to do exactly the timing or SDC comparisons I want than to figure out the circuit and component values for a 555 or op-amp.
For that matter, a 16 pin CH32V003 can emulate a vast array of 7400 series devices as long as you don't need ns timing — no problem for µs. It's also cheaper.
Using a cpu running software to emulate a handful of gates is just the furthest thing from interesting. It's the inverse of elegant.
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