Antenna structures with electrical connections to device housing members
Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include antenna structures that are formed from an internal ground plane and a peripheral conductive housing member. A conductive path may be formed that connects the peripheral conductive housing member and the internal ground plane. The conductive path may include a flex circuit. A metal structure may be welded to the peripheral conductive housing member. A solder pad and other traces in the flex circuit may be soldered to the metal structure at one end of the conductive path. At the other end of the conductive path, the flex circuit may be attached to the ground plane using a bracket, screw, and screw boss.
1. An electronic device, comprising:
a housing having conductive structures that form an antenna ground for an antenna and having a peripheral conductive member that runs around at least some edges of the housing and forms at least part of the antenna, wherein the antenna ground and the peripheral conductive member are separated by a gap; and
a conductive path that bridges the gap, wherein the conductive path includes a flex circuit that is attached to the peripheral conductive member, wherein the flex circuit comprises a flexible polymer substrate that bridges the gap, that contains at least one conductive trace, and that includes a solder pad electrically connected to the at least one conductive trace.
2. The electronic device defined in claim 1 wherein the gap comprises a dielectric-filled opening that includes at least some plastic.
3. The electronic device defined in claim 1 further comprising a metal structure that forms part of the conductive path.
4. The electronic device defined in claim 3 wherein the metal structure comprises a first metal coated with a second metal.
5. The electronic device defined in claim 3 wherein the metal structure comprises a metal plate.
6. The electronic device defined in claim 5 further comprising welds with which the metal plate is welded to the peripheral conductive member.
7. The electronic device defined in claim 6 further comprising solder with which the metal plate is connected to a trace in the flex circuit, wherein the trace forms part of the conductive path.
8. The electronic device defined in claim 7 wherein the peripheral conductive member comprises stainless steel and wherein the metal plate comprises a first metal that is at least partly coated with a plating layer of a second metal.
9. The electronic device defined in claim 7 wherein the metal plate has opposing first and second surfaces, wherein the first surface is attached to the peripheral conductive member and wherein the second surface has a solder-compatible coating to which the solder is connected.
10. The electronic device defined in claim 9 further comprising a screw and a bracket configured to attach the trace in the flex circuit to the antenna ground.
11. An electronic device, comprising:
a housing having a peripheral conductive member;
ground plane structures;
a metal member welded to the peripheral conductive member with welds; and
a flexible polymer substrate that contains at least one conductive trace that is connected to the metal member, wherein the at least one conductive trace comprises a solder pad and wherein the flexible polymer substrate extends between the ground plane structures and the metal member.
12. The electronic device defined in claim 11 wherein the solder pad is soldered to the metal member with solder.
13. The electronic device defined in claim 12 further comprising dielectric layer portions that overlap at least part of the solder pad and help prevent the solder from contacting the metal member in the vicinity of the welds.
14. The electronic device defined in claim 11 wherein the peripheral conductive member comprises a peripheral metal housing member having a rectangular ring shape.
15. The electronic device defined in claim 14 wherein the ground plane structures and at least part of the peripheral metal housing member form at least one antenna in the electronic device and wherein the electronic device further comprises:
a metal bracket interposed in an electrical path between the conductive trace and the ground plane structures.
16. The electronic device defined in 11 wherein the flexible polymer substrate comprises a flex circuit that contains the at least one conductive trace, wherein the metal member is interposed between the flex circuit and the peripheral conductive member, and wherein the metal member connects the conductive trace to the peripheral conductive member.
17. The electronic device defined in 11 wherein the conductive trace is soldered to the metal member.
18. The electronic device defined in 11 wherein the metal member comprises stainless steel coated with a plating layer.
19. The electronic device defined in claim 18 wherein the plating layer comprises a material selected from the group consisting of: nickel, tin, and gold.