555 Contest - Page 1
Forum section: electronics / projects

author: ChrisGammell
author_rank: Unknown
timestamp: January 23, 2011, 02:48:44 am
content: For all those that haven't heard, me and Jeri Ellsworth have set up a 555 design contest:http://www.555contest.com/Hope everyone is interested in participating! And tell your friends! The more the merrier!

author: Chasm
author_rank: Regular Contributor
timestamp: January 23, 2011, 03:57:03 am
content: I have just stumbled upon one of the more unsafe uses.A talk form DEFCON 17, "Injecting Electromagnetic Pulses into Digital Devices" at youtube. About 8min30 and onward.Really, that isnothow you want to do this, ever.

author: CafeLogic
author_rank: Regular Contributor
timestamp: January 23, 2011, 05:36:57 am
content: You should probably be aware of this:http://www.electro-tech-online.com/announcements/108585-competition-3-best-555-timer-project.htmlJust to make sure somebody does not rip-off one of these designs and try to submit it.

author: EEVblog
author_rank: Unknown
timestamp: January 23, 2011, 05:58:20 am
content: Quote from: ChrisGammell on January 23, 2011, 02:48:44 amBe careful what you wish for!(picturing Chris slogging through hundreds of entries wondering how he got himself into this mess!)Dave.

author: Zero999
author_rank: Super Contributor
timestamp: January 23, 2011, 01:55:47 pm
content: I used to like the 555 like lots of people but I now see it as obsolete and no, I'm not talking about replacing it with programmable devices.Don't get me wrong, it still has its place but I think hobbyists use it more than they should.Anyone read the article linked below?http://electronicdesign.com/article/digital/the-555-best-ic-ever-or-obsolete-anachronism-17718.aspxHere's a 555 timer design I came up with awhile ago. It dims a lamp using PWM. The difference here is it uses bootstrapping enabling an N-channel MOSFET to drive the high side. The circuit only needs two wires and can be simply connected in series with the load. The main disadvantages are it can never operate at 100% duty cycle and the load has to pass enough current to charge the capacitor. I'd recommend using a CMOS 555 timer but a standard TTL 555 can be used at the expense of the maximum duty cycle and the minimum load current.I've posted this circuit on other forums and decided to post it here, in case someone else enters it into the competition and takes credit for it, although I hope there'll be more innovative entries. lol

author: Simon
author_rank: Unknown
timestamp: January 23, 2011, 09:35:41 pm
content: I think you can get out of using that 4.7K resistor if your using the output to charge/discharge the cap

author: Zero999
author_rank: Super Contributor
timestamp: January 23, 2011, 09:50:36 pm
content: The 470R resistor is there to limit the maximum duty cycle. Without it, the output could be set for 100% duty cycle which would mean the power supply voltage to the 555 and MOSFET gate would fall too low for the MOSFET to be in the low resistance state causing it to get hot.

author: Zero999
author_rank: Super Contributor
timestamp: January 27, 2011, 06:21:35 pm
content: Quote from: Jack on SEtimesThat's a disappointment. I would've hoped it would be judged by an engineer.

author: ChrisGammell
author_rank: Unknown
timestamp: January 31, 2011, 04:11:19 am
content: Forgot about this post, whoops!It is being judged by an engineer as well, Hans Camenzind, the designer of the original chip. We're working on getting a couple other judges too, just in case Dave is right; don't want to let him sit there laughing while I judge hundreds of entries.

author: EEVblog
author_rank: Unknown
timestamp: January 31, 2011, 04:21:08 am
content: Quote from: ChrisGammell on January 31, 2011, 04:11:19 amDon't deprive me of that pleasure, please!Enter the contest everyone!Dave.

author: Time
author_rank: Frequent Contributor
timestamp: January 31, 2011, 02:10:51 pm
content: I must say, I am impressed with the prizes. I am sure this will turn up a lot of entries. This just means I know I don't have a snowballs chance in hell at winning something.What does a professional Eagle CAD license typically go for?

author: CafeLogic
author_rank: Regular Contributor
timestamp: January 31, 2011, 02:12:13 pm
content: Too Much

author: Zero999
author_rank: Super Contributor
timestamp: January 31, 2011, 05:12:40 pm
content: I'm definitely not entering then, firstly I don't think much of Eagle and secondly if I really wanted it that badly, I'd probably pirate it, like every other hobbyist.

author: Time
author_rank: Frequent Contributor
timestamp: January 31, 2011, 06:02:15 pm
content: I try not pirate stuff now that I am out of school and have a decent job. Though from a hobbyist stand point, CAD software is unsensibly priced even for someone very well off.

author: Zero999
author_rank: Super Contributor
timestamp: January 31, 2011, 06:20:05 pm
content: If it was good, reasonably priced and didn't watermark files created by it (allegedly) I wouldn't mind buying it but I've tried the free version and it's not worth pirating.CAD software developers don't care too much about hobbyists and students pirating their software: many of them will soon be professionals who'll encourage their employers to buy it.

author: Lance
author_rank: Frequent Contributor
timestamp: January 31, 2011, 10:54:58 pm
content: Pretty much, although it's still frowned upon.

author: Unknown
author_rank: Unknown
timestamp: February 01, 2011, 11:57:42 am
content: Cadsoft/Eagle probably care more, since they're not used that much in the professional world as far as I know, never heard from anyone outside hobbyist/semi-hobbyist (eg. Adafruit/Sparkfun) circles using it.

author: EEVblog
author_rank: Unknown
timestamp: February 02, 2011, 08:29:51 am
content: I just killed this 34 year old vintage Signetics 555 timer chip!R.I.PDOH!And I have video of it's final seconds.Who else can better a 1976 Signetics 555 in their parts bin?Dave.

author: saturation
author_rank: Super Contributor
timestamp: February 02, 2011, 12:29:46 pm
content: I have a National Semiconductor somewhere with the NS logo still on it, but it still works, last I tested

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 02, 2011, 01:42:03 pm
content: QuoteWeek 15 1976, and an Intersil one from '77

author: grenert
author_rank: Frequent Contributor
timestamp: February 05, 2011, 03:01:55 pm
content: The latest Nuts and Volts (February 2011) has a short story on modern updates to the 555.

author: monpjc
author_rank: Contributor
timestamp: February 05, 2011, 09:01:22 pm
content: Quote from: Hero999 on January 31, 2011, 05:12:40 pmAgree - tools should be ultra low cost or free.BTW - element14's prize is not first prize, there are plenty more stuff up for grabs.!

author: Mr J
author_rank: Regular Contributor
timestamp: February 05, 2011, 09:44:19 pm
content: I order about 2000 of the 555's a year. Can't wait to see some of the circuits, I'm trying to get one of my students to enter. I'll look around I think I have some NE555 from the 70's kicking around. Years ago I made one with discreet components.If your looking for a schematic capture program TinyCAD is free and works well for basic stuff. There is also a student version of NI multisim for around $30, just email a copy of you student ID. (I used my work ID and printed student on it, hi..hi).

author: FreeThinker
author_rank: Frequent Contributor
timestamp: April 27, 2011, 09:43:05 am
content: The 555 timer competition is now over but just came across thishttp://www.ordigami.net/timer555Do you think it would of qualified? It is certainly minimal

author: House91320
author_rank: Regular Contributor
timestamp: June 14, 2011, 03:27:02 am
content: I think i have one from 1973, am i correct?

author: Smokey
author_rank: Super Contributor
timestamp: September 23, 2014, 03:28:41 am
content: Looks like someone never planned on running another 555 contesthttp://www.555contest.com/