5:55 video released on May 5th, as per description :) For something feeling like a fairly specific IC, I remember seeing many projects that use it throughout the years in wacky ways - and seeing it makes me happy to know that the sentiment for this little piece is shared.
my favorite use of a 555 is in a solar charge controller. It is a voltage controlled switch!
i have the page archived, but it's called A New Solar _ Wind Charge Controller Based on the 555 Chip (2_7_2026 12
As a kid I didn’t understand what the 555 timer chip on the Apple II disk controller was doing but I learned the hard way that when you misalign the pins on the drive connector cable and the 555 chip releases its blue smoke you can’t use the drive anymore :(
Yea, definitely don’t let out the magic smoke. That stops all the fun right away.
I was on my college fencing team. One summer, I had an internship at HP and they paired me with a grizzled old hardware designer, Fred, as a mentor to build a summer project. Fred had a lab bench with drawers overflowing with old resistors, caps, ICs, and even some tubes (“Fred, what the hell are you going to use those for?” “You never know. Tubes might come back!”). Fred had once accepted a promotion to be a manager and quickly renounced it because he hated it and just wanted to design hardware. I decided to build the electronic scoring system used in fencing matches. Our school had one professional system, but I figured I could replicate it for a lot less money. It was all based on a couple of 555s, some 74-series TTL counters, a few LEDs, buttons, and a speaker. Fred was the guy who showed me how a 555 worked. I built it, it worked, and the school used it for at least a year or two after I left. Happy memories. God bless Fred, wherever he is.
I don't think you could do it. Not with the original BJT variant anyway. :)
Hmm, why not? For the astable configuration, you could use a 100F capacitor with R1 = 10 Meg and R2 = 7.5 Meg, for a 55 year period. Base current for the Threshold NPN will come from the Trigger PNP (and hopefully temperature drift matches OK). Other than maybe the 100F capacitor might have some variation in capacitance and leakage current over the course of 55 years ;-) https://www.digikey.com/en/products/detail/tec…
Once you get above a couple meg, the oils on your fingers start affecting the resistance. Better hope no-one touches with your 55 year counter
Evil Mad Scientist makes a giant, discrete version as a soldering kit: https://shop.evilmadscientist.com/productsmenu/tinykitlist/6... Very cool. (Looks like it uses 26 transistors. I assume the die is similar.)
I believe they based the design off of the reference schematic from a datasheet of one of the popular 555 timers, but I don't remember which one.
5:55 video released on May 5th, as per description :) For something feeling like a fairly specific IC, I remember seeing many projects that use it throughout the years in wacky ways - and seeing it makes me happy to know that the sentiment for this little piece is shared.
otoh i.m surprised the accelerometer was already available since 1927. since microcontrollers only the hardcore eecs kids build pid controllers from opamps for fun (only do hn on phone hard to link to that maker article of a fully analog segway where the writer missed the "analog" part and was like WOW a self balancing 2 wheeler by a grad student and not another baby's first Arduino bday kit
Another allrounder and close cousin in time and but with much more functionality is the 4046 CMOS Phase Locked Loop.
It can be configured as a versatile oscillator like the 555, but it can also implement an FM modulator / demodulator, a FSK modem, a tone discriminator, a clock multiplier, a phase detector, a voltage to frequency and frequency to voltage converter a speed control loop and much more.
Not bad for a $1 chip. My circuits professor always carried a bunch in his lab coat pocket and handed them out like candy almost everyone anyone needed a circuit to do something to do with oscillation.