PCB outer copper weight (1 oz vs 2 oz)? - Page 1
Forum section: electronics / general

author: [Chrille]
author_rank: Contributor
timestamp: August 02, 2021, 08:18:43 pm
content: I am about to order my first PCB from a PCB manufacturer but I am a bit confused about the option to get it manufactured with 2oz copper weight vs the standard 1oz outer copper weight.Is 1oz enough for a computer mainboard PCB? How much current can 1 oz carry?Thanks!

author: SteveyG
author_rank: Unknown
timestamp: August 02, 2021, 09:06:46 pm
content: 1oz is standard, but how did you design your track widths in the first place? You must consider the current to determine the track width at all points in the design.

author: IconicPCB
author_rank: Super Contributor
timestamp: August 02, 2021, 10:19:48 pm
content: Google PCB CALCULATOR. it will get you to an online utility which will guide You.

author: phil from seattle
author_rank: Super Contributor
timestamp: August 03, 2021, 01:13:15 am
content: What is the highest current you expect to see on your board? Even 1 Amp can be easily handled by 12 mil 1 oz copper trace.

author: [Chrille]
author_rank: Contributor
timestamp: August 03, 2021, 07:15:41 pm
content: Thanks for all of your replies!I Googled PCB calculator and found some online calculators that I used. The track width for the power supply rails of the PCB is 1.3 mm or about 50 mil, which should be more than sufficient for my needs as it seems. The maximum current that will pass through the circuit is 1.5 Amps.The calculator show different values for internal traces and external traces for the same current. But internal traces only apply to PCB's with >2 layers, right? The PCB I want to order is a 2 layer board so all traces are external.Please correct me if I am wrong

author: jusaca
author_rank: Unknown
timestamp: August 05, 2021, 09:02:58 am
content: Quote from:  on August 03, 2021, 07:15:41 pmYou are absolutely right. Internal traces are thermally better isolated due to the surrounding PCB material and heat up faster than external traces.

author: SteveyG
author_rank: Unknown
timestamp: August 06, 2021, 10:19:28 am
content: It still begs the question how have you designed a PCB without taking any of this into account?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 06, 2021, 03:15:40 pm
content: And a "computer mainboard PCB" at that? Is this one of the open source retro things and you're ordering some copies..?Tim

author: [Chrille]
author_rank: Contributor
timestamp: August 09, 2021, 06:43:33 pm
content: Quote from: SteveyG on August 06, 2021, 10:19:28 amI didn't design it. It is an open source project that someone else designed. The reason I asked is because I want to learn how stuff works. I want to get a board manufactured for personal hobby use. Nothing more advanced than thatAnd of course I would like to be able to create my own PCB designs for other projects in the future and you have to start somewhere, right?

author: Kean
author_rank: Unknown
timestamp: August 10, 2021, 03:32:05 am
content: So if it is an open source design, why not provide a link to it?Then people here would be able to give much more appropriate suggestions than guessing what your concept of a "computer mainboard PCB" might be.