How this ic work? - Page 1
Forum section: electronics / beginners

author: nhdyhh
author_rank: Newbie
timestamp: April 25, 2018, 11:12:33 am
content: helloHow this ic work in led display?https://assets.nexperia.com/documents/data-sheet/74HC_HCT04.pdfhttp://www.ti.com/lit/ds/symlink/cd74hc595.pdf

author: Rerouter
author_rank: Super Contributor
timestamp: April 25, 2018, 11:19:55 am
content: You really need to improve your questionThe 74HC595 chip is a shift-register, you feed it serial data, and it produces a parrellel output, likely used in an LED display to drive a large number of LED's from a small number of microcontroller pinsThe 74HC04 is an inverter chip, logic high becomes logic low, and vice-vesa, It again can be used to drive an LED that would draw more current than a microcontroller may be able to provide.

author: Rerouter
author_rank: Super Contributor
timestamp: April 25, 2018, 11:26:23 am
content: Sounds like your asking for there "Equivalent Circuits", or the parasitic information on the inputs and outputs?for the 595, look on page 9, If you need it broken down further, it gets more manufacturer dependent.https://www.onsemi.cn/PowerSolutions/document/MC74HC595-D.PDFfor the 74hc04, well this is very manufacture and series dependand, a good starting point would be this page,http://www.piclist.com/images/www/hobby_elec/e_sampl1_1.htm

author: agehall
author_rank: Frequent Contributor
timestamp: April 25, 2018, 12:41:00 pm
content: Sounds like it didn't take SDBFG long to register a new account...

author: rstofer
author_rank: Super Contributor
timestamp: April 25, 2018, 01:35:31 pm
content: Quote from: agehall on April 25, 2018, 12:41:00 pmAnd apparently OP has missed out on the Google thing.

author: Brumby
author_rank: Unknown
timestamp: April 25, 2018, 01:43:52 pm
content: Quote from: agehall on April 25, 2018, 12:41:00 pmSo ... I'm not the only one wondering about this.

author: hexreader
author_rank: Frequent Contributor
timestamp: April 25, 2018, 01:58:00 pm
content: I am guessing that you are still trying to build a large moving-message LED display?Is it mono or colour display that you intend to build?How many dots wide?How many dots high?What physical size (height and width)?74HC595 is just a cheap and simple way to gain a lot of outputs from an MCU with few spare pins. It can be used in many, many, different ways.

author: wraper
author_rank: Unknown
timestamp: April 25, 2018, 02:41:21 pm
content: Don't bother replying in this thread, as OP is just yet another spam account.

author: BravoV
author_rank: Super Contributor
timestamp: April 25, 2018, 02:52:53 pm
content: Quote from: Brumby on April 25, 2018, 01:43:52 pmFirst few encounters could be exciting or even fun, just wait until flock of them joined here, really hope not.Just pity the mods team if this happened.

author: BravoV
author_rank: Super Contributor
timestamp: April 25, 2018, 03:03:09 pm
content: Quote from: wraper on April 25, 2018, 02:41:21 pmActually not spamming, its just the attitude that is like dumping what ever popped out in their mind, or they like or feel like without any consideration at all, and usually comes with very demanding request like the community owe the OP.And if not answered, they just love to bombard with new threads again and again on the same subject, or worst keep bumping the thread every hours ... for weeks.Oh ... also usually these people will not happy if the responds are not they like to hear, and will keep nagging again and again.Really wish I am wrong , but its just the fact I have seen for years at so many nice forums they've trashed.

author: Simon
author_rank: Unknown
timestamp: April 25, 2018, 03:12:52 pm
content: There is the option to ignore them.... let the thread die

author: wraper
author_rank: Unknown
timestamp: April 25, 2018, 03:15:23 pm
content: Quote from: BravoV on April 25, 2018, 03:03:09 pmCurrently it's not, but will be in the future. IMO this is to get post count high. Yesterday apparently the same person asked more than 10 unrelated useless questions before got banned.

author: BravoV
author_rank: Super Contributor
timestamp: April 25, 2018, 03:16:58 pm
content: Quote from: Simon on April 25, 2018, 03:12:52 pmI have done that at many forums that I used to hang out, but at the end once you are overwhelmed by the SNR that is so low beyond your sensitivity level, and also once the mods show the sign of giving up, usually its a sign to leave, which I really hate.

author: ebastler
author_rank: Super Contributor
timestamp: April 25, 2018, 03:23:12 pm
content: Quote from: Simon on April 25, 2018, 03:12:52 pmShort of blocking the OP (yet), could you lock those threads?

author: BBBbbb
author_rank: Unknown
timestamp: April 25, 2018, 03:26:02 pm
content: Quote from: wraper on April 25, 2018, 03:15:23 pmMy thoughts exactly.Probably selling some scam stuff, and just trying to build up post count / rep. Person(s) behind it are not too familiar with electronics and English, but they are trying at least...

author: amyk
author_rank: Super Contributor
timestamp: April 26, 2018, 12:30:20 am
content: Quote from: wraper on April 25, 2018, 03:15:23 pmGiven that he seems to be honest about his country (unlike some other more aggressive spammers we've seen before), I don't think he's aiming to spam. Just a typical persistent dullard.Perhaps the registration form should detect specific "problematic" countries (either self-selected or by IP), and give those users a basic knowledge quiz... something easily Googlable, not too hard but not too easy (1+1=?). There's a certain repair forum which does a similar thing.nhdyhh , pleasedo the needfulbefore trying to post again.

author: BravoV
author_rank: Super Contributor
timestamp: April 26, 2018, 12:45:16 am
content: Quote from: amyk on April 26, 2018, 12:30:20 amThis is not easy, as it feels like stereotyping, and could spark pros & cons, even among mods themselves. Its a concerning matter for sure.Quote from: amyk on April 26, 2018, 12:30:20 amDamn, its infectious.

author: BravoV
author_rank: Super Contributor
timestamp: April 26, 2018, 06:21:37 am
content: Quote from: BravoV on April 25, 2018, 03:03:09 pmEnough said ->https://www.eevblog.com/forum/repair/help-needed-to-repair-hp-spectrum-analyser/msg1497331/#msg1497331PS : Actually I do have tons of fine examples in this forum alone, its just not worth it to dig them out.

author: Simon
author_rank: Unknown
timestamp: April 26, 2018, 06:40:47 am
content: Quote from: BravoV on April 26, 2018, 12:45:16 amIt would be completely the wrong approach, the biggest problem user we ever had was from the UK, so do we blacklist the UKanother nightmare member was from Germany..... The quality of the forum depends on the how people use it including how much they feed trolls or make nonsensical threads the hottest thread in town and then complain that this "spam" keeps coming up. We tend to err on the safe side and people don't get banned for asking the odd silly question, being silly does not break any rules.

author: BravoV
author_rank: Super Contributor
timestamp: April 26, 2018, 09:57:09 am
content: Quote from: Simon on April 26, 2018, 06:40:47 amAgree, as I said, its not easy to make a conclusion and decision out of these.Quote from: Simon on April 26, 2018, 06:40:47 amI guess one or two incidents for few days or per week are still manageable and not a big deal from moderator's POV.Its just I wish you guys mods never have to live thru the hell if this expands into multiple folds in magnitude.Thank you Simon for all your time & energy in taking care of this unpleasant matter, just want you to know that I do appreciate what you've done here.

author: Simon
author_rank: Unknown
timestamp: April 26, 2018, 10:02:00 am
content: We have had a spat of chinese posters just putting copy paste stuff up to later add links in their sig but they seem to have given up. If someone does create a load of nonsensical posts they will get removed, we can be tolerant of ignorance but after lets say 3 nonsensical topics the difference between ignorance and spam is pretty clear.

author: tggzzz
author_rank: Super Contributor
timestamp: April 26, 2018, 11:33:34 am
content: Quote from: Simon on April 26, 2018, 06:40:47 amFor the record, although I might not always have made the same decisions you (lot) do, I haven't seen anything boneheaded - and I think you (lot) do an excellent job.Keep it up, please.