Reply 20 of 87, by feipoa
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- l33t++
There should be some general guidelines or calculations for what wire guage to use for what current and for run lengths at DC. Generally, though, you can get some estimate for the thickness of the traces, their lengths, and try to at least use equal wire cross sectional area.
For AC, I think there are also guidelines for current capacity and run length based on operating frequency. I remember something called the skin effect which states that the majority of current runs along the surface of the conductor, and the amount is a factor of the frequency. Maybe this is where the benefit if stranded wire comes in? I haven't really researched this much recently.
Concerning the inductors - I cannot say for certain because I just formulated this theory and have begun implementing it. I replaced the 4 uH keyboard inductors on my board with 2.2 uH and didn't notice any issue. The fact that the board manufactures go the extra step (sometimes) to put 1 uH for the mouse and 4 uH for the keyboard does have me curious. I have noticed, though, that many motherboard manufacturers merely follow the circuit implementation example provided by the manufacturer of some device, e.g. the keyboard controller, voltage regulator datasheet, etc.
Plan your life wisely, you'll be dead before you know it.