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Topic: modifications of barebone arduino (Read 8606 times) previous topic - next topic

GoForSmoke

great news.. I set chip to 8Mhz internal oscillator did the whole process and its working :) .so I have got rid of my crystal osciallator and 22Pf capacitors, my barebone chip looks more compact now..Now I will test it 4.5V batteries 1.5x3 AAA and use power saving mode jeelab which i have already used in my code..and now test the battery life . With the voltage regulator it lasted 4days, now lets see how long will it last since now I have removed regulator and crystal .

I will have a look at voltage converters after I test the battery life. Thanks
Just for fun, try 2 AAA batteries/3V test.
If you need longer life, put batteries in parallel.
1) http://gammon.com.au/blink  <-- tasking Arduino 1-2-3
2) http://gammon.com.au/serial <-- techniques howto
3) http://gammon.com.au/interrupts
Your sketch can sense ongoing process events in time.
Your sketch can make events to control it over time.

Adey

Yep I did try for 3V as well i.e AAAX2(1.5x2) and its working fine. Unfortunetly I dont have a battery pack with me to permanently fix the batteries. Probably have to find one of those or make up. Also worked with 4.5V. Should I go with 4.5V right as it has a higher voltage. And why do i need to connect in parallel. Isnt voltage same in parallel. I need to connect in series right  :o .

GoForSmoke

3V might also run SD where 4.5V would have to be voltage leveled.

You would need 4 batteries to do 3V parallel, 2 in series connected parallel with 2 in series.
The current draw would be shared. If you need to run on batteries then 4 lasts twice as long as 2.
1) http://gammon.com.au/blink  <-- tasking Arduino 1-2-3
2) http://gammon.com.au/serial <-- techniques howto
3) http://gammon.com.au/interrupts
Your sketch can sense ongoing process events in time.
Your sketch can make events to control it over time.

Adey

Iam sorry but what do you mean  by SD..is that required on my breaboard...and 4.5 V need to  be voltage levelled..again can you explain what you actually mean by its need to be voltage levelled...

polymorph

I would not put cells in parallel. Better to just use larger cells. We kinda hashed this to death in another thread.
Steve Greenfield AE7HD
Drawing Schematics: tinyurl.com/23mo9pf - tinyurl.com/o97ysyx - https://tinyurl.com/Technote8
Multitasking: forum.arduino.cc/index.php?topic=223286.0
gammon.com.au/blink - gammon.com.au/serial - gammon.com.au/interrupts

GoForSmoke

#35
Nov 21, 2014, 04:26 pm Last Edit: Nov 21, 2014, 04:27 pm by GoForSmoke
SD is Secure Digital data card, what you stick in phones, cameras, MP3 players, tablet PC, netbook, PC, data loggers, etc.

SD adapter is what you connect to Arduino if you want to store and/or read much data.

They come in physical different sizes and capacities, a 2 gigabyte card is only a few $, I paid $30 for 10.

You could $10 to $20 for a shield or you can make your own cheap. To make your own you buy a microSD card with full size SD adapter sleeve as shown here

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2882538&CatId=3610

The little piece is the micro data card that fits microSD slots. The big piece is what the little one fits to let it be used in full size SD slots.

The cool part is that the big piece has contacts you can solder to on the back side. Then you put the micro card in and you have an SD adapter. If you buy a shield you still need to buy a card.

The SD card normally with Arduino gets run at 3.3V but probably works good on 3V. Any more than 3.7V will probably burn it up. Running SD on a 5V Arduino takes circuits to lower the 5V signals to 3.3V range and that is called voltage-leveling since it changes the voltage level from 5V to 3.3V.

BUT if you run at 3.3V and very likely 3V, you can wire directly from your AVR to the adapter!

Consider the limited memory on your AVR, what having megabytes to gigabytes of "hard drive" can let you do. SD is the means of choice to log data on remote collectors.

But be aware that the SD library and SPI library are needed and they use almost half the RAM on a 328P chip with default setup.
1) http://gammon.com.au/blink  <-- tasking Arduino 1-2-3
2) http://gammon.com.au/serial <-- techniques howto
3) http://gammon.com.au/interrupts
Your sketch can sense ongoing process events in time.
Your sketch can make events to control it over time.

Adey

I didnt really require  SD card when I made my previous barebone...I dont think it was causing any problem. My barebone arduino will just transmit data x times a day. Thats pretty much it. The storing of data would be done on the reciever side by the RF module reciever(which would be linked to an uno).

Guys I need help regarding power supply. I want my power supply to last the longest. Yes I have added power saving Jeelib for now for the software part in my arduino code( I wil get to power saving modes once I get this work done. Probably start a fresh post on power saving techniques on the software part.)

But on the physical side, going by common sense I would probably require a larger current deliverance. So at 3V my barebone  its working. At 4.5V also its working. Its AAA batteries iam using. So I should i just go with 1.5V x3 = 4.5v in series. However that would only supply current equal to one cell. So two batteries in parallel connected in series with another two batteries in parallel. That would give me 3V with current utlization of all 4 cells.

Any help on right combination??


GoForSmoke

#37
Nov 22, 2014, 02:42 am Last Edit: Nov 22, 2014, 02:43 am by GoForSmoke
Can the unit get sunlight? Or wind? Or hot and cold or steady vibration?
1) http://gammon.com.au/blink  <-- tasking Arduino 1-2-3
2) http://gammon.com.au/serial <-- techniques howto
3) http://gammon.com.au/interrupts
Your sketch can sense ongoing process events in time.
Your sketch can make events to control it over time.

mrburnette

Quote
Guys I need help regarding power supply. I want my power supply to last the longest
You need to do some research.
The problem all designers of battery devices, all chemical technologies, is that voltage is not constant as the batteries age.  AA batteries have significant more stored chemical energy, so unless size absolutely mandates AAA cells, use AA.

The use of 2 cells or 3 cells must be considered not in terms of initial terminal voltage, BUT terminal voltage under peak load during the battery useful life cycle.  As batteries age (become depleted) the terminal voltage lowers and the internal resistance goes up (not desirable attributes.)

Lookup the battery chemistry and model (AA, AAA) and take a view of the curve slope over time.  Find the voltage at which your circuit ceases to work then look at the life line (in hours, percent, etc.). Using the current line for your circuit while it transmit, calculate the battery time for always on.  Then extend that time by the percentage of OFF time to get an estimate.  For example, if the circuit powers up once a minute for 5 seconds, then the multiplier would be 12 for every minute... Therefore for nominal current applications, if full-on would give 24 hours, multiply this by 60 to get minutes and multiply by 12 to get estimated run-time minutes.  As they say, your results may vary.


Ray

Adey

Can the unit get sunlight? Or wind? Or hot and cold or steady vibration?
Well Iam not allowed to give details about the project, but the barebone chip would be installed in manufactering a plant inside an enclosed deviced. So yeah you can say no sunlight, no wind, vibration yes definitely...

Adey

You need to do some research.
The problem all designers of battery devices, all chemical technologies, is that voltage is not constant as the batteries age.  AA batteries have significant more stored chemical energy, so unless size absolutely mandates AAA cells, use AA.


Yes all that can be done, even better would be actually do it practically. Power one chip with 3V AAA batteries, another one with 4.5V and compare the results. Size constrain is an issue in our project and so is cost. I need to ask my senior if we can fit in AA batteries.

Anyways I ill start off with 3X 1.5AAA and 3X1.5 AA batteries and then compare. Can anyone how to connect three batteries in series, I mean in an efficient way, not by using tape and all that..cause I tried that yesterday, tapes keep coming off, its not just compact.

GoForSmoke

If there is active vibration more than very low level, that can be tapped for small energy using piezos. But hey the small energy all the time X many collectors could build enough to power a low power circuit that is off most of the time.

If you have a heat differential and Peltier wafers then you may be able power even more. Consider the girl in Canada who won the science fair with a flashlight that is powered by the heat of her own small hand. That flashlight doesn't shine seconds out of a minute though the beam is weak.

Either way would need a boost converter rather than buck converter.

Do it right and you can save having a person check and change batteries regularly.

This works with regular diodes. It would work better for small taps with Schottky diodes but with strong vibration the voltage produced may be too much for those.
https://www.youtube.com/watch?v=ReN_QU78pcs

I've used this circuit to flash a led with a single finger tap and brightly with a single screwdriver handle smack.  :smiley-evil: Honest, I was just testing suitability!  :smiley-twist:

It is also what powers leds in kids shoes that helps them be seen at night by car drivers when they run out in the street. Compare the energy in the steps of a small child to the energy in your steady vibration.

The power is very low per squeeze but vibration is squeezes per second. Put the disc on the vibrating surface and a mass or mount on the other side and see what 1 disc can harvest. That would be for 1 disc. A Joule Thief can boost that steady low V to higher V charging pulses.

If you have something that shakes then magnets and coils also become an option.

Instead of tape you can use big heat shrink tube to make batteries into a pack.
If you have a constant power trickle input, use a super-capacitor to store instead of batteries.
1) http://gammon.com.au/blink  <-- tasking Arduino 1-2-3
2) http://gammon.com.au/serial <-- techniques howto
3) http://gammon.com.au/interrupts
Your sketch can sense ongoing process events in time.
Your sketch can make events to control it over time.

Adey

I would not put cells in parallel. Better to just use larger cells. We kinda hashed this to death in another thread.
larger cells as in how much voltage you talking about??

Paul__B

If you want it to run on the UNO board then it must be 16MHz external crystal or resonator.
Just browsing through this somewhat tedious thread, I felt it appropriate to mention that this is not strictly correct.

A chip set for 8 MHz internal oscillator will run just fine in the UNO board, it will simply ignore the presence of the crystal.  Any sketch already loaded will work, however the "identity" is that of the chip, not the board, so to actually download to it, you need to call it something else, such as an 8 MHz Pro Mini.  Actually, I think you need to call it whatever the bootloader that is on that chip, was purposed for.

GoForSmoke

Wow, Paul! News to me and Karma to you!
1) http://gammon.com.au/blink  <-- tasking Arduino 1-2-3
2) http://gammon.com.au/serial <-- techniques howto
3) http://gammon.com.au/interrupts
Your sketch can sense ongoing process events in time.
Your sketch can make events to control it over time.

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