How to design the five common drilling methods of PCB manufacturers

118 Drone Boards (6)

1: Hole types are divided into: over the hole (Vai), plug-in holes (Pad holes), no copper mounting holes (Npth) over the hole (via): just the role of electrical conduction does not have to plug the device welding, the surface can be done to open the window (pad exposed), cover oil or plug oil. Plug-in holes (Pad holes): need to plug in the device welding pin hole, the pad surface must be exposed. No copper mounting holes (Npth): screw holes or device plastic fixing feet, no electrical properties, to play a role in locating fixed

2: Hole properties, board factory hole definition has two properties, metal and non-metallic. Most of the metal holes are device pin holes, part of the metal screw holes, up and down to electrical conduction. Non-metallic holes are holes that do not have a copper wall up and down the non-conductive holes, also known as mounting holes. Metal holes and non-metallic holes in the attributes of the difference between the “Plated” whether or not there is a check mark, if the hole check the “Plated” then the hole attributes for the metal, if you do not check the non-metallic holes is non-metallic holes, non-metallic holes normally have no outer diameter. (The figure below shows the settings for metal holes)

3: Spacing of perforations

a: over the hole (Via) and over the hole (Via) spacing between: the same network over the hole edge spacing ≥ 8mil (0.2mm), different network over the hole edge spacing ≥ 12mil (0.3mm).

b: plug-in holes and plug-in spacing between: hole edge spacing ≥ 17mil (0.45mm), the limit of 12mil. plug-in holes Pcb production drilling will be pre-sized 0.15mm under the drilling, drilling and then sinking on the copper, and ultimately to ensure that sinking copper after the aperture and the design of the finished hole in the Pcb the same size. (Hole edge spacing 0.45 = 0.15 hole compensation + 0.1 hole ring + 0.1 hole ring + 0.1 safety spacing, unit mm)

c: near the hole on the impact of production: two holes too close will affect the PCB production drilling process. Two holes too close will drill the second hole on one side of the direction of the material is too thin, uneven force on the drill bead and the drill bead heat dissipation is not the same, which leads to break the drill bead, which causes the PCB hole avalanche is not beautiful or leakage of drilling holes do not lead.

5. metal half-hole and stamp hole metal half-hole: metal half-hole is the most common pcb board factory called, there are many hardware engineers will call him “stamp hole”. The center of the metal half-hole needs to be drawn in the center of the profile line, half inside and half outside the board. The minimum hole diameter of the half-hole is 0.5mm, the edge of the hole to the edge to ≥ 0.5mm. stamp holes: the board factory so-called stamp holes is to bridge the role of the board without copper holes, also half in the board and half outside the board. Stamp hole size is generally 0.5mm copper-free holes, edge spacing is 0.3mm (center distance 0.8mm) 5 holes or more than 5 number of a group (according to the size of the board and whether there is a heavy device to add more holes.) According to the size of the board with stamp holes connected to the splicing plate, the location of the holes after the split plate will have convex burrs, if the shape of the structural requirements of the strict requirements can not have protruding burrs, then you can add the stamp holes to the direction of the board in the direction of the point.