Electrical Engineering

3:42 AM

Hiya

I want to use a single GPIO pin, to provide 'Enable' signal to 3 other devices, one after the other, with slight delay. Would an inductor with a flyback-diode be a acceptable way of achieving something like this ?

The Photon

4:00 AM

@icarus74 I'd rather go with a "one-shot" or monostable multivibrator.

Actually you'd need 2 or 3 of them, but they're cheap. Probably cheaper than inductors.

icarus74

Umm... as in done using 555 ? Or a dedicated IC ?

The Photon

You can use a 555 but there's lots of newer alternatives:

ti.com/lsds/ti/logic/monostable-multivibrator-products.page

I've used 74LV123 before (IIRC) but they all work essentially the same.

No I'm wrong, I'm pretty sure I used 74LVC1G123...but you might rather use a dual package for your job.

icarus74

Ok.. lots of options

However, I need PHT components... so with min 14pins, it seems to take a bit of space. Cascading 3-4 of them will quickly fill up board space.

The Photon

@icarus74 Looks like you can get a dual in a 16-pin DIP... you'd probably only need two chips to manage 3 signals...assuming the first one goes immediately when the uC tells it to.

icarus74

Right.

thanks @Photon

The Photon

4:08 AM

RC delay and schmitt-trigger buffers is another option...depending how long a delay you want and how fussy you need to be about getting the delay exactly right.

icarus74

Delay between triggers I am looking at is around 100mS with tolerance of about 20%

Sorry, bad math... delay of about 400mS with tolerance of about 10%

user61389

5:06 AM

@NickHalden I'm going to study it, how's that? Nothing really specific, but I like ethics (especially political stuff) and philosophy of logic and language. So what's your connection with philosophy?

Nick Halden

5:46 AM

@CamilStaps Nothing really, I just find some philosophical topics absolutely fascinating

For example, try defeating the argument that all humans are ethically selfish

Ayn Rand turned me onto the discussion and it's really interesting. It's pretty much impossible to prove that altruism exists...

@CamilStaps I never studied it or anything, just read some books and have done a lot of thinking

jippie

6:07 AM

@DavidKessner This guy is trying to better his life wit ATtiny's. We should give him a chance.

good morning @guys

Nick Halden

@jippie So I've been up for 20 hours right now

is it still morning???? I feel like @AnindoGhosh.....

jippie

@NickHalden I stopped worrying about the time of day (at least here in chat).

Nick Halden

@jippie but don't you have to go to work at certain hours? that

is the only reason i keep a schedule at all...

now excuse me while i drank some caffeine

jippie

I usaually go to work about 9:30'ish. But today I have lot of other things to do, so I took the day off

Nick Halden

@jippie ah nice, i haven't used a vacation day yet... and ive been working for about 10 months so i should have a pretty decent amount saved up

over 2 weeks actually, cuz i get 15 days / year

user61389

6:12 AM

@NickHalden cool! Good to know I'm not a total loony combining electronics and philosophy ;) fortunately it's equally impossible to prove that egoism exists, or at least is our only drive, like some think

jippie

@NickHalden we have 26 days/yr and I bought 10 extra.

Nick Halden

@CamilStaps yeah, but unfortunately for my peace of mind, that seems the more likely one...

@CamilStaps but i dont have time to discuss right now =/ i have a deadline in 7 hours, lets talk another time about it?

user61389

@NickHalden I can understand that, it feels more likely to me too. Yes, very well!

Nick Halden

alright cheers y'all, back to work i go

jippie

enjoy @NickHalden

user61389

6:24 AM

Let's see what's happening at school.. see you!

abdullah kahraman

6:37 AM

@CamilStaps Me too have school today!,

jippie

6:50 AM

everybody leaving me!?

user61389

@abdullahkahraman I don't really, but I want to have the feeling to be somewhat prepared for my exams. :) fortunately there isn't really anything happening here, so I'm back! (@jippie)

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