How to determine the appropriate width of the tracks while designing board?

[yasser_shoukry]

I want to know how to determine the appropirate width of the tracks while designing my board.
For instance, i am designing a board that has 6 H-bridge(which is used to control DC motors), each H-bridge is capable of driving the motor with max 6 Amperes, so in the worst case about 36 Amp will flow in the board, what the appropirate width of the power tracks to suite these conditions

Best Regards,
Yasser

 

[kender]

Re: Track Width

Look up IPC-2221A standard in this forum. In that standard there is a chart that tells you the trace width from the current, copper thickness (in oz) and ambient temperature. Also, Google "trace width calculator" - there is a number of web-based calculators for the trace width.

Here's an example of the trace width calculator:
http://www.geocities.com/capecanaveral/lab/9643/TraceWidth.htm

 

[centiago]

Re: Track Width

By rule of thumb, 1 mm trace @ 1 Oz copper carries 1 Amp of current.
You can increase the current carrying capacity by
a> increasing copper thickness (2 Oz or more)
b> increasing trace width & multiple trace at different layer.
c> open soldermask the outer track

In case of multi Layer board, Trace thickness in inner layers shoudl be 1.25 times higher, it's because it needs to dessipate heat.

In case of A/C section maintain a gap of 6 mm between Live & Neutal & 7 mm between Live & Earth.

In case of DC, maintaining a gap of 1 mm is sufficient. Avoid loop current while routing.

This should take care of your problem.

 

[dfullmer]

Re: Track Width

This seems to work.

It also seems to coroborate kender's trace width calculator.


dfullmer