Minimum track width is the minimum width of electrical copper features on the layer. Minimum clearance is the minimum spacing between copper features on the layer. Minimum annular ring is the minimum ring width (pad radius minus hole radius) around plated holes on the layer.
The Macaos Enterprise Import Module estimates the minimum feature sizes of your imported product files. These estimates are accurate in most cases, but it is not possible for the system to make an accurate estimate in every situation.
Minimum track width and minimum annular ring are estimated by performing a simple analysis of the imported copper and drill layer data. Minimum clearance is estimated to be the same as the minimum track width. These estimates will be correct in most cases, but some CAD systems generate their trace and/or pad data in a manner that is too complex and time-consuming for the rapid analysis performed by the Import module.
If you know that one or more of the estimated values are incorrect, you should enter the correct values as necessary.
Incorrect minimum feature values will not affect the manufacture of your PCB, but they might lead to incorrect price quotations. In many cases, manufacturers will charge somewhat higher prices for minimum features less than 0.15 mm.
Minimum feature values are also related to copper thickness. In general, minimum track width or clearance on a copper layer may not be less than about 2 to 3 times the copper thickness of that layer. If the estimated minimum track width or clearance is too small for the copper thickness of the stackup you have selected, then you will need to enter the correct value before publishing the product.
The actual minimum feature sizes are always checked (and corrected, if necessary) by an engineer once an order has been placed. If necessary, you will be notified as to price changes or copper thickness incompatibility.