You'll find some details in 'Camenzind Oral History'[0] around page 4 (seems he got paid and it was a good arrangement, but there was no patent on the 555).
Note that while the 555 is definitely a classic, definitely an amazing and useful chip, it puts large current spikes on the power supply and you would probably want to use something else in new designs unless you’re feeling nostalgic.
Replacing a 555 timer is a very common job for this type of part. It will typically have an internal oscillator, so it won't need the additional components the 555 needs, reducing cost further. Even if you use something more expensive like an ATtiny (cut down version of the microcontroller found in Arduinos, so very easy to develop for) it might still be competitive because of the reduced parts count and board space.
Hmm. The argument for using a microcontroller to replace a 555 is the increase complexity, and risk. There is code to be written, programming process install at manufacture etc. So it is not necessary cheaper if you at a level higher than the BOM cost.
This was the first IC I ever saw, when I was pulling apart busted electronics equipment in the early 1970s. I understood why transistors had three leads, but what the heck could possibly need eight leads?!?!?
I loved this part. It was the second chip my dad let me use as a kid (after the 741) and IMHO he should have given them to me in the opposite order since the 555 seemed more magical and fascinating for a child.
Amazing. I remember 555 monostable and astable multivibrator and PLL were classic school projects. First simulation in P-Spice followed by implementation on bread-board.
As far as I know they just used whatever number they wanted, leading to confusing situations where one producers ' 4736 (made up, no idea if this one exists) would be a totally different thing from another's 4736. You'd keep them apart by the manufacturer code, i.e. FOO4736 = 'double-width gizmotron' while BAR4736='confufabulator (4ch)'. I used to leaf through catalogues looking for 'interesting' circuits and came across quite a number of such confusingly-named parts.
Well you also have to remember that companies came and went faster than startups did. And consolidation happened quite quickly as well. Engineers made cool things but only a handful of the companies found a hit, and rarely did the same company consistently find the best. What ended up happening is the bigger companies just started buying the small company that had the hit that year. The old model was no more sustainable than the current model.
Along with what baybal2 says today they'd have to fit in to a corporate environment that rewards credentials over demonstrated skills, gladhanding and backslapping over geeking, financial engineering over the creation of tangible things.
Yes, and Bob Widlar too. That was the early days of integrated circuits though, and in the early days of any field it's often the mavericks and non-conformists who make the most progress.
Actually, Hans Camenzind was pretty busy up until the day he passed away in 2012. He continued to do analog circuit design, among other things (like writing books). (Good) analog engineers are not that common these days. At one point in the mid-2000's he mentioned to me that of his 15 most recent circuit designs, not one had an issue post-initial design. I don't think a lot of analog engineers today could say that. I suspect if he was still around and looking for work, he would not have much trouble finding it.
These days I usually just drop in a 6 pin microcontroller though. Less external parts, cheaper, less environmental instability, much more operational flexibility, and often I can have it perform several circuit functions. If I go to 8 pins, woah, look out!
I do so much digitally now that I've "forgotten" 75 percent of my analog stuff... Once in a while I come upon a cool analog trick though. Sad part is, that usually the "super simple, bulletproof" analog solution with just 5 parts usually ends up being more expensive in qc, bom, and board space that throwing a million transistors at it.
Those transistors can drive 60V and 1A; hardly any controller can do such things. You might expect some special controller pins to drive e.g. 100 mA at 5V; more often, something like 20 mA at 3.3V.
Is this for a production device or like a hobby type thing? Reason I ask is that I'm often resistant to adding auxiliary microcontrollers to things just due to the extra hassle of maintaining, building, and distributing the firmware for them. Like, even if it's a device with JTAG, that's still a program-once-in-the-factory affair, unless you go the trouble of also setting up an SPI bootloader or something on it.
I guess the counter argument is that a 555 circuit can't be reprogrammed either, but it also doesn't have to be programmed even the first time.
With analog solutions, the complexity gets pushed into designing the test rigs, validating your component supply, thermal compensation, etc. Dealing with firmware instead may or may not be a net win, but the bottom line is you can change the firmware but you can't change the board.
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[ 3.1 ms ] story [ 97.8 ms ] thread*[0] http://www.semiconductormuseum.com/Transistors/LectureHall/C...
EDIT: Found it! it looks like the bold parts are "microgramma" and the less bold looking parts are "eurostile."
https://www.youtube.com/watch?v=VYhAGnsnO7w
Replacing a 555 timer is a very common job for this type of part. It will typically have an internal oscillator, so it won't need the additional components the 555 needs, reducing cost further. Even if you use something more expensive like an ATtiny (cut down version of the microcontroller found in Arduinos, so very easy to develop for) it might still be competitive because of the reduced parts count and board space.
http://www.analog.com/media/en/technical-documentation/data-...
There are many better alternatives now.
https://www.electronicdesign.com/boards/555-best-ic-ever-or-...
https://shop.evilmadscientist.com/productsmenu/652
https://www.youtube.com/watch?v=U6qZPx4uD0g
http://www.designinganalogchips.com/
Work culture in America has changed since sixties.
Companies now trust marketing/sales boys to know the market better than the very people who made that industry.
In sixties, a CEO comes to an engineer and asks what will be the "next bug thing" in one year term.
Today, a CEO comes to an engineer and tells him what will be the "next bug thing" in one year term.
Taken to its logical extreme you get Theranos. Will lessons be learned? I’m not holding my breath.
These days I usually just drop in a 6 pin microcontroller though. Less external parts, cheaper, less environmental instability, much more operational flexibility, and often I can have it perform several circuit functions. If I go to 8 pins, woah, look out!
I do so much digitally now that I've "forgotten" 75 percent of my analog stuff... Once in a while I come upon a cool analog trick though. Sad part is, that usually the "super simple, bulletproof" analog solution with just 5 parts usually ends up being more expensive in qc, bom, and board space that throwing a million transistors at it.
It's a strange world we live in.
https://www.mouser.com/ProductDetail/Diodes-Incorporated/ZXT...
https://www.mouser.com/ProductDetail/Microchip-Technology/PI...
Notice that the discrete transistors actually cost more than the microcontroller.
https://www.youtube.com/watch?v=0fKBhvDjuy0
Those two transistors had better be hella good to justify the price difference.
I guess the counter argument is that a 555 circuit can't be reprogrammed either, but it also doesn't have to be programmed even the first time.