PTH Annular Ring (Drill)

Reports the shortest distance between drill and laminate for PTHs embedded in copper if less than pp_d2c.

Internal ERF Name	<Area>:pth2t (from pth to thermal)
Measurement Shape Measurement ID	Segment In negative power and ground layer, Entity = thermal pad, or Entity = clearance if clearance encroaches on drill. In positive power and ground layer, there is no Entity.
Layers Displayed	Power and ground layer Drill layer piercing it
Graphic
Purpose	A hole connected to copper must have a sufficiently large annular ring of copper. If not, shifts of the drill and the imaging process cause the drill to lack sufficient contact.
Function	Reports the shortest distance between drill and laminate for PTHs embedded in copper if less than pp_d2c. Breakouts are allowed by specifying a breakout angle between 0 - 180 where 0 = no breakout. In most cases these drills are drilled through thermal pads; the annular ring indicates the quality of the connection. With negative power and ground layers, the associated entity from the power and ground layer is a thermal pad. See “Annular Ring Measurement”.
ERF Parameters	pp_d2c
ERF Variables	classify_via2t pth_breakout_angle
Constraint	Plated Hole AR
Limitations	In positive power and ground layers, no associated copper features are reported.