TABLE OF CONTENTS Standard PC boards are generally fabricated from epoxy-fiberglass, phenolic fiber, or polyimide. The copper surface conductor is bonded to the surface of the board and is available in single- or double-sided form.
The copper conductor surface is available in the following standard weights and thicknesses: oz, 0.00067 in; 1 oz, 0.00135 in; 2 oz, 0.0027 in.; and 3 oz, 0.004 in.
Table 6.26 shows the current-carrying capacity for different track widths in copper weights of , 1, and 2 oz. Note that the relationship between track width and current capacity is not strictly linear, but is close enough to being so that we can interpolate between the values shown to determine track widths for intermediate current values.
| Track width, in | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| -oz Cu (0.00067 in) | 1-oz Cu (0.00135 in) | 2-oz Cu (0.0027 in) | |||||||
| Current, A | 60 C | 30 C | 10 C | 60 C | 30 C | 10 C | 60 C | 30 C | 10 C |
| 0.125 | 0.003 | 0.003 | 0.003 | 0.002 | 0.002 | 0.002 | 0.001 | 0.001 | 0.001 |
| 0.200 | 0.005 | 0.005 | 0.005 | 0.004 | 0.004 | 0.004 | 0.003 | 0.003 | 0.003 |
| 0.500 | 0.015 | 0.010 | 0.007 | 0.008 | 0.006 | 0.004 | 0.005 | 0.004 | 0.004 |
| 0.750 | 0.030 | 0.020 | 0.016 | 0.015 | 0.010 | 0.007 | 0.008 | 0.006 | 0.006 |
| 1.00 | 0.040 | 0.030 | 0.025 | 0.025 | 0.015 | 0.010 | 0.012 | 0.008 | 0.008 |
| 1.50 | 0.065 | 0.040 | 0.034 | 0.030 | 0.020 | 0.013 | 0.015 | 0.010 | 0.011 |
| 2.00 | 0.090 | 0.050 | 0.042 | 0.045 | 0.025 | 0.016 | 0.022 | 0.013 | 0.013 |
| 3.00 | 0.125 | 0.060 | 0.050 | 0.060 | 0.030 | 0.020 | 0.030 | 0.017 | 0.015 |
| 5.00 | 0.250 | 0.125 | 0.095 | 0.130 | 0.060 | 0.040 | 0.070 | 0.034 | 0.025 |
| 7.00 |
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