Circuit Boards Specifications

  Standard Advanced
Annular Ring
Internal Minimum Pad Size .016" larger than finished hole size .014" larger than finished hole size w/teardrop
External Minimum Pad Size .016" larger than finished hole size .014" larger than finished hole size w/teardrop
Increase pad size accordingly for annular ring requirements greater than .001"
Holes requiring greater than .001" copper (i.e. 1oz plated to 3 oz Finish) require and additional .004 pad diameter.
Plane Layer Clearance
PTH & NPTH Hole Clearance to Plane .030" larger than finished hole size .024" larger than finished hole size
PTH & NPTH Hole to Inner Layer Trace .015" Spacing .012" Spacing
Line Width and Space
Inner Layer Line width on H ounce copper Minimum -.004" Minimum - .004"
Inner Layer Line width on 1 ounce copper Minimum-.005" Minimum-.005"
Inner Layer Line width on 2 ounce copper Minimum -.008" Minimum -.008"
Inner Layer Line width on 3 ounce base copper or greater Minimum -.012" Minimum -.012"
Outer Layer Line width on H ounce base copper Minimum-.004" Minimum-.004"
Outer Layer Line width on 1 ounce base copper Minimum -.005" Minimum - .005"
Outer Layer Line width on 2 ounce copper Minimum -.008" Minimum -.008"
Outer Layer Line width on 3 ounce base copper or greater Minimum -.012" Minimum -.012"
Inner layer Feature to Feature on 1 ounce or less base copper Minimum -.005" Minimum - .004"
Inner layer Feature to Feature on 2 ounce Base Copper Minimum -.008" Minimum -.008"
Inner layer Feature to Feature on 3 ounce copper or greater Minimum -.012" Minimum -.012"
Outer layer Feature to Feature on 1 ounce or less base copper Minimum -.005" Minimum - .004"
Outer layer Feature to Feature on 2 ounce Base Copper Minimum -.008" Minimum -.008"
Outer layer Feature to Feature on 3 ounce copper or greater Minimum -.012" Minimum -.012"
Trace to Plane Spacing Minimum -.008" Minimum -.008"
Feature to Board Edge *does not include tabs Minimum -.010" Minimum -.008"
Feature to Score Edge Minimum -.020" Minimum -.015"
Solder Mask
LPI Conductor Overlap .015" Larger Than Feature Size .010" Larger Than Feature Size
LPI Mask Clearance .015" Minimum .013" Minimum
LPI Mask Web .005" Minimum .005" Minimum
Less than 4 mil web between component pins may result in loss of mask between SMT pads.   Decrease clearance to 5 mil, then web to 3.5mil, then clearance to 4 mil, etc.
Silkscreen
Silk Screen Ink .008" minimum aperture .006" minimum aperture
Copper Features (ETCHED TEXT) .010" minimum aperture .010" minimum aperture
Font Height .065" minimum height .045" minimum height

If the specifications of a board design fall into the advanced category it may be subject to additional charges.

America's Oldest, A History of Innovation.  Learn More →
Our History

As the oldest production Printed Circuit Board Company in North America, perhaps in the world, the 60-year plus story of Epec is connected to the development of the PCB and the electronics industry.

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  • Epec Founded in 1952
  • IPC Founded in 1957
  • Epec Builds PCB for Apollo 11