PCB trace
From HwB
(Difference between revisions)
(Completely rewritten) |
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== Graph == | == Graph == | ||
| − | === Outer traces ( | + | === Outer traces (0-1 A) === |
<gnuplot> | <gnuplot> | ||
| − | set output ' | + | set output 'PCB_trace_outer2.png' |
set terminal png notransparent interlace size 800,400 enhanced | set terminal png notransparent interlace size 800,400 enhanced | ||
set size 1.0,1.0 | set size 1.0,1.0 | ||
set grid x y | set grid x y | ||
| − | set ytics 0, | + | set ytics 0,1 |
| − | set xtics 0,1 | + | set xtics 0,0.1 |
set xlabel "Current [A]" | set xlabel "Current [A]" | ||
set ylabel "PCB trace width [mils]" | set ylabel "PCB trace width [mils]" | ||
| − | plot [x= | + | plot [x=0:1] (((x/(0.048*10**0.44))**(1/0.725))/1.378) title "10 degrees C", (((x/(0.048*20**0.44))**(1/0.725))/1.378) title "20 degrees C", (((x/(0.048*30**0.44))**(1/0.725))/1.378) title "30 degrees C" |
</gnuplot> | </gnuplot> | ||
| − | === | + | === Outer traces (1-10 A) === |
<gnuplot> | <gnuplot> | ||
| − | set output ' | + | set output 'PCB_trace_outer1.png' |
set terminal png notransparent interlace size 800,400 enhanced | set terminal png notransparent interlace size 800,400 enhanced | ||
set size 1.0,1.0 | set size 1.0,1.0 | ||
set grid x y | set grid x y | ||
| − | set ytics 0, | + | set ytics 0,10 |
set xtics 0,1 | set xtics 0,1 | ||
set xlabel "Current [A]" | set xlabel "Current [A]" | ||
set ylabel "PCB trace width [mils]" | set ylabel "PCB trace width [mils]" | ||
| − | plot [x=1:10] (((x/(0. | + | plot [x=1:10] (((x/(0.048*10**0.44))**(1/0.725))/1.378) title "10 degrees C", (((x/(0.048*20**0.44))**(1/0.725))/1.378) title "20 degrees C", (((x/(0.048*30**0.44))**(1/0.725))/1.378) title "30 degrees C" |
</gnuplot> | </gnuplot> | ||
| − | === | + | === Inner traces (0-1 A) === |
<gnuplot> | <gnuplot> | ||
| − | set output ' | + | set output 'PCB_trace_inner2.png' |
set terminal png notransparent interlace size 800,400 enhanced | set terminal png notransparent interlace size 800,400 enhanced | ||
set size 1.0,1.0 | set size 1.0,1.0 | ||
| Line 64: | Line 64: | ||
set xlabel "Current [A]" | set xlabel "Current [A]" | ||
set ylabel "PCB trace width [mils]" | set ylabel "PCB trace width [mils]" | ||
| − | plot [x=0:1] (((x/(0. | + | plot [x=0:1] (((x/(0.024*10**0.44))**(1/0.725))/1.378) title "10 degrees C", (((x/(0.024*20**0.44))**(1/0.725))/1.378) title "20 degrees C", (((x/(0.024*30**0.44))**(1/0.725))/1.378) title "30 degrees C" |
</gnuplot> | </gnuplot> | ||
| − | === Inner traces ( | + | === Inner traces (1-10 A) === |
<gnuplot> | <gnuplot> | ||
| − | set output ' | + | set output 'PCB_trace_inner1.png' |
set terminal png notransparent interlace size 800,400 enhanced | set terminal png notransparent interlace size 800,400 enhanced | ||
set size 1.0,1.0 | set size 1.0,1.0 | ||
set grid x y | set grid x y | ||
| − | set ytics 0, | + | set ytics 0,25 |
| − | set xtics 0, | + | set xtics 0,1 |
set xlabel "Current [A]" | set xlabel "Current [A]" | ||
set ylabel "PCB trace width [mils]" | set ylabel "PCB trace width [mils]" | ||
| − | plot [x= | + | plot [x=1:10] (((x/(0.024*10**0.44))**(1/0.725))/1.378) title "10 degrees C", (((x/(0.024*20**0.44))**(1/0.725))/1.378) title "20 degrees C", (((x/(0.024*30**0.44))**(1/0.725))/1.378) title "30 degrees C" |
</gnuplot> | </gnuplot> | ||
Revision as of 20:28, 27 January 2007
According to IPC-2221 (formerly IPC-D-275, MIL-STD-275)
Below table is valid for:
- PCB material FR-4
- Board thickness=1.6mm (0.063")
- Trace thickness=35µm (1 oz)
- Allowed temperature rise=10 °C
Contents |
Table
| Current | Width (inner) | Width (outer) |
|---|---|---|
| A | mils | mils |
| 0.01 | 0.308 | 0.118 |
| 0.05 | 1.54 | 0.591 |
| 0.1 | 3.08 | 1.18 |
| 0.2 | 6.15 | 2.37 |
| 0.4 | 12.3 | 4.73 |
| 0.4 | 12.3 | 4.73 |
| 0.5 | 15.4 | 5.91 |
| 0.6 | 18.5 | 7.1 |
| 0.7 | 21.5 | 8.28 |
| 0.8 | 24.6 | 9.46 |
| 0.9 | 27.7 | 10.6 |
| 1.0 | 30.8 | 11.8 |
Note: 1 mil = 1/1000" = 0.0254 mm
Graph
Outer traces (0-1 A)
Outer traces (1-10 A)
Inner traces (0-1 A)
Inner traces (1-10 A)
Formula
Given:
- I [A] (Current)
- T [°C] (Temperature rise)
- m [oz] (Mass of PCB trace)
Constants:
- y = 1.378 [mils/oz] for copper
- b = 0.44
- c = 0.725
- k = 0.048 (for outer layers)
- k = 0.024 (for inner layers)
Formulas:
- A [mils²] = <math>{(\frac {I}Template:KT^b)}^{\frac {1}{c}}</math> (PCB trace area)
- l [mils] = <math>\frac {A}{m y}</math> (PCB trace width)