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
Guys I need help regarding power supply. I want my power supply to last the longest
Can the unit get sunlight? Or wind? Or hot and cold or steady vibration?
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.
I would not put cells in parallel. Better to just use larger cells. We kinda hashed this to death in another thread.
If you want it to run on the UNO board then it must be 16MHz external crystal or resonator.