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555 Timer Circuits

(www.555-timer-circuits.com)
280 points okl | 1 comments | 17 Oct 24 18:30 UTC | HN request time: 0.203s | source
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tdeck ◴[19 Oct 24 21:54 UTC] No.41891054[source]▶
Here's my tip for the 555 timer: Learn what's inside it! As you can see on the "Inside the 555" page, there are fewer than 10 functional components inside and three of them are resistors.

For some reason I always struggled to remember the different operating mode configurations, what they are called, and how to set them up. But one day I was trying to build a specific thing and decided to sit down and actually understand the 555. To my surprise, it's really simple in operation and requires relatively little electronics theory to understand and derive the different configurations yourself. Once I did that, I haven't forgotten it and I can come up with more creative uses for the 555.

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Stratoscope ◴[20 Oct 24 01:25 UTC] No.41892161[source]▶
The Evil Mad Scientist kits are a great way to learn what's inside it. They are faithful replicas of the internal 555 circuitry, built with discrete transistors and resistors.

You mentioned only ten functional components inside it, but if you look at individual transistors and resistors, there are quite a few more.

Here is the through-hole component version:

https://shop.evilmadscientist.com/productsmenu/652

And a surface mount device version:

https://shop.evilmadscientist.com/productsmenu/922

I built the through-hole version, and it worked the first time I wired up a circuit around it.

Highly recommended!

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1. NikkiA ◴[20 Oct 24 04:33 UTC] No.41892881[source]▶
'10' would be counting the comparator and 2 op-amps as 3 components, the replicas you're pointing at break those out to discretes too, because once you've started down that road, why wouldn't you?