According to Pete 10-2-11: 555 Timers

[daafies2]

mono what?

[KD0IDB]

"Guess that song..." LMAO!

[paziipa]

Dude! Talk about flipflops!

[123456789robbie]

dude. talk about flipflops.

[123456789robbie]

9:40 "obviously" XD

[bos4t]

Couldn't you use the 555 as a battery monitor/charger alarm circuit with few external components?

[thewii552]

Flip-flops and instrumentation amps please!

[CliffordWolf]

Obviously the formula for the frequency should be 1/(ln(2)*C*(R1+2*R2)), which is 1/(t_h + t_l). Your formula is just 1/t_h which can't be right..

[Tuchmanlaw]

Great video. The 3 resistors are 5k each. That's why they named the chip 555.

[snoeg]

Just noticed that on the whiteboard T_high is the multiplicative inverse of frequency f. So, I looked at wikipedia and it seems that in the frequency equation instead of just R2, you should have 2 * R2. Just thought I'd point it out :)

That being said, these videos are great! Looking forward to see more of this "analog stuff" :)

[HampusSandberg]

Pete do you think you could talk about decoupling capacitors sometime? Thanks!

[umdmrlbro]

Lookin good pete!

[Geving]

Dude! Talk about flip-flops!

[LithiumLogica]

Just as with the Make Magazine channel's Collin's Lab and Fritz's The Latest in Hobby Robotics, your information videos on Sparkfun are a favorite of mine. Very well put-together, informative, and you present the information in understandable terms.

Your videos tend to feel a little more technical, but that's good. Means I have a little work to do figuring out the few things you don't go into intricate detail(the flip-flop, for example).

Thanks and keep it up! Really enjoy the vids.

[ElectroCilph]

flipplops in the top comments? My head hurts now. It's flip-flop. Latch if level-sensitive.

[tagno25]

The LM555 has three 5k resistors. You can see the entire schematic on National's website

[MichaelJE2]

Can you PLEASE fix your A/V sync? In the wide shot his mouth is moving, and then a half a second later I can hear what he said.

[shiftplusone80]

To everyone saying flipplop... *flip-flop.

[febvigrail]

I've been trying to figure these things out for the past week! Perfect timing on this video. :D

[fezrichard]

Thanks Pete, another great episode.

[dmt195]

With small pics being so cheap and easy these days, what's the advantage of using a 555?

[tagno25]

@dmt195 no programming and fast circuits

[emactan]

@dmt195 absolutely none :p And some PICs even have an SR latch to emulate the 555

[Snowkakegubbe]

MO-NO-STA-BLEH

heh nice one pete

[foreverwii]

talk about making more advanced synths!

[scopeeyevideo]

For the astable configuration you gave "time high" as

Th=ln(2) * (R1+R2) * C1

and "time low" as

Tl=ln(2) * R2 * C1

The equation you gave for frequency is equal to 1/Th... Shouldn't it be equal to 1/(Th + Tl)? So instead of this:

f = 1/(ln(2) * C1 * (R1 + R2))

it should be this?

f = 1/(ln(2) * C1 * (R1 + 2*R2))?

[juanpabloish1]

flipflops please Pete!

[SebiTimeWaster]

Kill me!!!

[roymesi]

dude, talk about flip flops!

[Albinorama]

please talk about something that Internet is not flooded/spamed.

Whats next?Arduino?...c'mon....

[bswain9999]

nice

[DjViOd]

You should totally check the Class T audio amplifiers from 41hz. com

[megasmart1337]

talk about flipplop's

[arots]

i thought the resistors were 5k

[bbmanpoison]

@arots Yep they are, and were on datasheets I looked at O_o

[LukeeeeBennettPlus]

@cyrilxdj A flipflop, is the use of 2 logic gates to store data. A simple google search will go a long way. :)

[Andromedan]

Those 3 resistors are 5KΩ in the original IC design.