The room we’re saying in is #555.

Some folks would think it’s easy to remember because it’s just three fives.

Nope.

Well, yes, it it just three fives… but it’s also one of the most famous integrated circuits in the world. The 555 is an astable multivibrator — a fancy way of saying a “timer chip.”

It’s been estimated that over 1,000,000,000 of these guys are manufactured every year.

I have a couple in my parts bin, along with it’s bigger brother the 556 which is nothing but a pair of 555s crammed into one package.

Yes. I understand I’m a weird one… I’ll do a post (or maybe even a video or something) on the 555 some time. Until then, I’ll leave you with Dave Jones’ version.