Introduction

Edge connectors are generally used for connecting one PCB to another, the edge connector is plugged in to a socket on another PCB thus making the connection.

Examples of this can be seen on a computer motherboard where you plug a graphics card with a gold edge connector into the socket on the mother board.

edge connector

Example of an Edge Connector on a PCB



Edge Connector viewed in a CAM system

Example of an Edge Connector viewed in a CAM system


The surface finish of edge connectors is usually with what is known as Hard Gold on top of nickel, this allows for the repeated plugging and unplugging of the connector.

To help guide the edge connector into the socket they need to have a bevelled leading edge.

Edge connector bevel profile

Example of the Bevelling of an Edge Connector

Specification

Description
Specification
Maximum Pad Length40mm
Inner layer Copper to Board Edge Clearance20o – 3.00mm
30o – 2.00mm
45o – 1.00mm
60o – 1.00mm
Minimum Finger WidthSee our   Classification Table   for the minimum Outer Layer Track width (OTW) and Track to Track (TT) distance
PTH to Edge Connect Clearance (edge to edge)2.00mm
SMD Pad to Edge Connect Clearance (edge to edge)2.00mm
Copper Feature to Edge Connect Clearance (edge to edge)2.00mm
Minimum PCB Thickness1.00mm
Maximum PCB Thickness3.20mm
Minimum Remaining Material Thickness – All Angles0.25mm
PCB Dimension Perpendicular to Edge Connector for Standard BevellingMinimum – 40mm
Maximum – 400mm
Bevel AngleStandard – 30o
Special – 20o, 30o, 45o, 60o
Distance between Edge Connectors on Opposite side of the PCB150mm
Customer Panel LayoutSee Panel Guidelines

Bevelling

Also known as chamfered edges.

Copper-Clearance-Bevel-Angles-for-Edge-Connector

Bevelling angles with minimum inner layer copper clearance


There are two types of bevelling available for edge connectors as below:

Standard
  • Standard bevelling is machined on the bevelling machine.
  • Only 30 degrees angle possible.
  • Only possible for edge connectors on an accessible outside edge of a single PCB.
  • The PCB dimension perpendicular to the bevelled edge must be minimum 40mm and maximum 400mm.
Special
  • Special bevelling machined on the rout machine.
  • Available at angles of 20, 30, 45 or 60 degrees.
  • Bevelling is Special it cannot be done on the bevelling machine:
    • Bevelling “inside” of an accessible outside edge of a PCB.
    • Bevelling “inside” of the PCB contour.
    • PCB dimension perpendicular to the bevelled edge less than 40mm or more than 400mm.
    • Bevelling on PCBs in a customer panel.
    • Other than 30 degrees angle.

Copper Clearances

Outer Layer Clearances

Do not place any plated holes (PTH), SMD or other pads closer than 2.00mm (Dimension D) to the inner edge of the edge connector fingers.

Copper Clearance on Inner Layers

The minimum copper free area on inner layers is to prevent exposed inner layer copper at the bevelled edges.

Inner Layers with Copper Free Area

Inner-Layer-Edge-Connector-with-Clearance

Inner layer with copper free area (example 2.00mm at 30 degrees angle (CAM image)



Copper-Clearance-Bevel-Angles-for-Edge-Connector

Bevelling angles with minimum inner layer copper clearance


Inner Layers without Copper Free Area

Inner-Layer-Edge-Connector-No-Clearance

Inner layer without copper free area (CAM image)



Exposed-Inner-Layer-Copper-Bevel-Angles-for-Edge-Connector

Exposed inner layer copper after bevelling with copper free area on inner layers