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What could I do with 100 ne555p IC's? Answered

I ended up with 100 NE555P IC'S and don't know what to do with them besides try to sell them. I'm thinking about making a PWM power supply just to tinker with, so there's 2 down. Any ideas for something practical or neat?

Here is the date sheet:NE555P http://www.componentschip.com/details/Texas-Instruments/NE555P.html


8 Replies

iceng (author)Josehf Murchison2017-06-10

Good one Joe. I do not have the calculator math features, but I have some Signetic's page data...

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Josehf Murchison (author)iceng2017-06-11

I have an Excel page I made you enter R1, R2, and C1 in the cells and it gives you the frequency, duty cycle, time off, and time on.

You can enter the value of C1 and the frequency and it gives you the resistor values.

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Jack A Lopez (author)2017-06-09

I think you should keep a significant fraction of them, like 1/4 or 1/2, or all, because they come in handy for different things, particularly that pair of comparators that compares an input voltage to 1/3 and 2/3 of the supply voltage. It is handy for debouncing a switch, or for sort of cleaning up an analog input, like the voltage on a phototransistor in a photogate. You know, you kind of want it to be a digital signal, high or low, and turn a messy analog signal into something with square corners.

Regarding selling them, I am kind of reminded of the words of Marsellus Wallace. He said that in his line of work, he was surrounded by a lot of "unrealistic" individuals who believed what they had to sell would, "age like fine wine", but in truth, this was really not the case.

Well, 555 ICs do not age like fine wine, or renaissance paintings, or antique cars, or any of that stuff like that. Actually, the character of these ICs do not really seem to change at all really, over like decades, maybe centuries, at room temperature.

I remember one time, some physics professor was telling me, and the rest of the class, that microscopic transistors do go bad, slowly, as a consequence of diffusion of the dopant atoms from N-doped silicon regions to adjacent P-doped regions, but I think he said this kind of corruption was worse for super-tiny scale transistors, like those found in bleeding edge microprocessors. Also the rate of diffusion was faster at higher temperatures. So a microprocessor, at its normal, hot, working temperature, would experience much faster dopant diffusion than a cold microprocessor, chillin at room temp, still new in the cardboard and anti-static-plastic box.

The point of my story is I think the only harm in keeping your old 555s around, is they take up space, I guess. But not too much space, compared to like the size of a house or apartment.

However, if you're living in something the size of a car or van, or if you're homeless and all your material possessions can fit into a volume smaller than a stolen shopping cart, then, in that circumstance, maybe they might take up too much space, and the money you could get for them would truly be more useful.

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Vyger (author)Jack A Lopez2017-06-09

You have become a little more philosophical lately with your answers. You stuck inside somewhere hold up because of the heat with nothing constructive to do? Or just getting more reflective on life? I would like to develop a tandem system for my shopping carts. A bar connecting system that allows the owner to push from the inside, between the 2 carts rather than being vulnerable to attack while pushing from behind. It would also defend against sneak attacks from those little yappy dogs. Add some spikes to the wheels so they get all poked when trying to run between the wheels. And I definitely need a mount for a GPS and a few solar panels overhead for keeping things charged. Ohhh , need to switch out the hard rubber/plastic wheels with inflated ones for stealth cruising . Hard wheel carts make a lot of racket. They are designed that way so they can keep track of you in the store. That is why its hard to get away more than one of them at a time.

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Jack A Lopez (author)Vyger2017-06-10

I think the phrase is, "holed up",


and, you're right. Some of the answers I'm writing are getting weird. I should probably take a break from this forum, and go play outside. In the morning part of the day, it is not too hot for that.

Regarding your shopping cart plans, what can I say, besides, "Shine on you crazy diamond!"


Also on the subject of shopping carts, I just noticed this old 'ible,


is about to turn10 years old. The "posted" field says, "Jun 28, 2007"

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rickharris (author)Jack A Lopez2017-06-10

Nooo, your all I look for :-)

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seandogue (author)2017-06-09

they're cheap as dirt. Hold onto them for future use.

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