sorry, but i didn't find a clear answer to this. now, that i want to move from usb to standalone, i just want to be sure before burning the thing.
edit.. forgive me... right after asking i found an answer by using other search terms. i'll use a regulator and go to vin
It is the same. But it is better to power the module using the VIN
FFracaproject:
It is the same.
How can they be the same, when if you power via the 5V pin has to be a properly regulated 5V and via the Vin pin, 7-12V?
elloPropello:
i'll use a regulator and go to vin
Why don't you get a 5V phone charger / power pack / wall wart and shove it in the usb socket? (As long as it's a proper usb compliant 5V.)
Power WHAT ?
Where's the schematic ?
What are adking about , the arduino ?
If so you should either use 5V to the Vcc pin or 7 to 9V to the Vin.
The Stepper needs a separate 12V supply.
It's not s good idea to power the arduino Vin
ftom the stepper 12V because the 5V regulator
will get hot dissipating the 7V difference.
FFracaproject:
It is the same. But it is better to power the module using the VIN
They're NOT the same. There are different markings at those pins for a reason. Vin goes through a linear regulator; 5V goes direct to the controller.
Best is indeed 5V to the 5V pin, and the same 5V to all other 5V peripherals. The Vin may be convenient for prototyping, don't think I've ever used it, tbh. Mobile phone charger, USB from the computer, 5V breadboard supply... all are easier to come by than a 7-9V supply. Or 12V to buck converter to supply 5V to the rest of the circuit. Come to think of it the other day I found a 9V supply in a drawer, and I also have an old 9.5V laptop supply.
For a stepper indeed a separate 12V supply. An old 19V laptop supply works wonders, too.
i was really refering to the arduino nano itself. because i want to use it inside an eurorack module, i want to use the available power rail. so i thought it would be best to take the +12 power rail, a 7805 voltage regulator and i guess a 100n capacitor to ground wouldn't do much harm, too.
should have been more precise in the opening post i guess.
a 7805 voltage regulator
Not a good idea for reasons already explained.
When you post on the forum please actually READ (ALL) of the replies.
What does it say about what you just said ?
raschemmel:
Not a good idea for reasons already explained.When you post on the forum please actually READ (ALL) of the replies.
What does it say about what you just said ?
i have no idea. everytime some electronic component in an eurorack module needs 5v there is a 7805 regulator used. so it cannot be that wrong to think about using it. i am just doing it for fun. mainly i am doing music and this is my first attemt in using an arduino for my modular setup. so, i am by no means an experienced electronic student or such. i have a soldering iron, built some modules. some burnt, but most work. i have not really the indepth understanding of what is going on inside, but i somehow am able to create own circuits... when i come along questions i cannot answer by myself, i search the internet or ask in forums, so i don't have to invent the wheel again. if that is wrong on this forum, i apologize
i have no idea. everytime some electronic component in an eurorack module needs 5v there is a 7805 regulator used. so it cannot be that wrong to think about using it
Yes it can.
Read Reply #4
What does it say about running a 7805 from 12V ?
raschemmel:
Yes it can.
Read Reply #4
What does it say about running a 7805 from 12V ?
sure, i got that. would a voltage divider help to get around that? i guess i'll breadboard it and check if it gets hot or not.
You can't use a voltage divider.
You need a buck converter to lower the voltage to 7.5V
elloPropello:
i have no idea. everytime some electronic component in an eurorack module needs 5v there is a 7805 regulator used.
I had to look that one up - it's a synthesizer, that makes a big difference. Linear regulators are popular in the music world there as they provide a more stable output, no high frequency noise as you see on the output of a buck converter.
It also depends on what current this component draws. 100 mA is about the limit without much of a heat sink - that's 700 mW dissipation. If that 7805 is mounted onto the chassis, that's acting as heat sink and you can draw double the current before it overheats. A more modern approach would be to use a 12V-7V buck converter, and that 7V noise and all into a 7805 (or one of the many more modern regulators, it's an old design) to produce a very stable 5V supply. 100 nF is not enough; see data sheet for required input/output capacitors.
In comparison, a halfway decent buck converter can deliver 1-2A of current at 5V without even getting warm, drawing less than half of that current from the 12V input.
thank you. never heard of buck converters... i'll check that out
Similar to (same as?) switching power supply.
wvmarle:
Similar to (same as?) switching power supply.
my modular synthesizer is powered by a switching power supply
Literally switching power supply.
"If it ain't switching, it's not a buck.."
(actuallly 'buck ' means a downconverter
(ie: 12V=>5V), whereas a 'Boost' is an
upconverter (ie: 5V=>12V) . But you're
probably one of the ole die hards that
"would rather fight than switch !".
BTW, he's right, if you have a 200lb frame heatsink
you don't have to worry about heat because
the 7805 won't get all hot and bothered...
it is one of these: https://shop.befaco.org/555-large_default/switched-power-supply-pb5.jpg
Buck.
Do you have a place to mount a 7805 regulator
?
raschemmel:
Buck.
Do you have a place to mount a 7805 regulator
?
yes, sure i have. understanding the difference between a buck converter and a regulator is beyond my understanding (the ones i just found online seem to use voltage regulators as well). but since it sounds reasonable to go for such a buck converter, i will try to wrap my head around it. in the past i never had issues using a 7805 regulator with my cmos projects. but i trust your knowledge on the arduino stuff since i definately don't want to blow mine up.
