Hi,
My circuit has an input of 3V provided by a little Button Cell Battery and the default size width of the Net/connection lines is 0.33 mm, how do I decide what is the right width size for connections?
Thanks

 

first determine what is the worst case current for that circuit. this will control smallest trace width for your Cu thickness (usually 1oz/ft^2)
but that may result in trace that is way too thin for manufacturing or... too expensive to manufacture. in that case feel free to increase trace width to practical/affordable size.

 

i use KiCad which has trace calculator built in. Not sure if your software has it or not but here is handy online calculator:
http://circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/

 

i use KiCad which has trace calculator built in. Not sure if your software has it or not but here is handy online calculator:
http://circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/

Hi "panic mode", thanks for the information. I use PCB Maker (or call it as DipTrace). I don't know about its calculator, I will check it. Also, I just noticed that PCB s/w allows a Min of 0.203 for the width size of the traces/connections!