Arduino Uno to ATmega328 - Shrinking your Arduino Projects

Posted by: @sumanta

@codecage 

Watch the above video. It's said there.

@sumanta, if you watch and listen to the video/audio in the lesson, note the use of words "Probably" and "Usually" - which only imply that they have a higher chance of having the bootloader. It is not a rule per se.

@sid 

Yes. That's right.

I had a small question. Can I use a USB power supply with the Arduino made on the breadboard using the FTDI adaptor? Or the FTDI adaptor can only be used for uploading the code?

@sumanta

Though I have not been using FTDI on too many occassions, I would only go for using it to upload codes to the ATMEGA chip.

The Pro Mini of Arduino (and probably some others - I am unsure of this "others") did not have any USB power or any other power input (as a barrel jack). Power needed to be supplied via the pins on the board. So it was either battery cells or FTDI Basic - more here - https://learn.sparkfun.com/tutorials/using-the-arduino-pro-mini-33v/all

And if you dont want to hop on to that link, here is the important section from the page -

There is a third power option that's only usually available while you're programming the Pro Mini. The FTDI Basic Breakout can be used to power the Mini via your computer's USB port. Keep in mind that this option may not be available when your project has entered the wild, absent from any computers or USB supplies.

@sid

Posted by: @sid

I would only go for using it to upload codes to the ATMEGA chip.

Okay. But can I use it to power the circuit? Is the process viable?

Posted by: @sumanta

@sid

Posted by: @sid

I would only go for using it to upload codes to the ATMEGA chip.

Okay. But can I use it to power the circuit? Is the process viable?

I am not sure on that. But here are some things that you should consider-

1. Using FTDI to power - will need your component/product to be hooked up to some power source.

2. FTDI will not be able to generate the mA needed for Arduino Mega/Uno (again, I am not sure)

3. You would port your program to ATMEGA only for the sake of making it lightweight. Using FTDI will only add more components and weight.

4. If you have more components attached and they all need power, it is not any good to use FTDI for power supply.

So I think it would all depend on the concerned project.

@sid

Thanks for these tips. 😀 

@sid

Okay. I will use external power supply. Which is better to use: 6V battery pack (1.5*4=6) or 9V battery?

@sumanta

I think we are still discussing about ATMEGA328 and if so, as per the data sheets - Vcc 1.8V to 5.5V. Absolute maximum 6V.

If you are using an Arduino Uno, it has circuitry on board that can handle 12v inputs maximum. And many say, you should never exceed that as well. The official recommended range is between 7 to 12 volts  for Arduino Uno, but works good with the USB supply from Laptops which is normally around 5v.

@sumanta, Sid is correct.  You're going to want to add a regulator to the setup.  Simplest is probably the 7805, 5 volt regulator.  You'll need to put 7 volts in to that one as a minimum to get the 5 volts you want. It's only one of many types but common and available in thru hole type package. (TO 220)

@sid

I want to make my projects mobile, so that I can carry it wherever I want. So, this cancels out USB power supply from PC. I don't have a power bank also. Leaving this, I have 2 options left:-

1.

6V battery pack (1.5*4=6)

2.

9V battery with battery cap. If I use this with the ATMEGA328, then I will need a voltage regulator.

So, what's your opinion on this matter. Which of the above power supply should I use with the ATMEGA328 acting like an Arduino on the breadboard?

@sumanta

The voltage regulator is REQUIRED to regulate the voltage of your power supply down to the 5V needed by the ATmega328.  Your first choice above will only supply 6V to the 7805 regulator, so it is a NO GO as the 7805 will require at least 7V to regulate down to 5V.  However, your second choice delivers 9V (at least while the battery can supply at least 7V) so should would.  How long the battery works depends on the current drawn from the battery.

Okay then. I will use the 9V battery. Thanks for the suggestion. 😀 

@sumanta One other option is to go 6 cell, with rechargeable.  That would put you at 7.5 volts, resulting in less heat for the regulator to dissipate, and less money spent overall on batteries after a few recharges. (rechargeable cells being around 1.25 volts each.)

@centari

Yeah. But I will have to purchase them separately. Presently, I have only these options. I want to make my project with the resources, which I presently posses and see how it goes.

Anyways, thanks for the suggestion 😀 

@codecage

I had a question. The voltage regulators step down the voltage to 4.96V and not 5V. Will it be a problem in powering the ATMEGA328?