Embedded and printed acoustic port
Described are techniques for creating acoustic inlet manifolds for a microphone that utilize existing flex or printed circuit board (PCB) technology to create an ultra-low profile manifold. The described techniques: take advantage of the ability to allow reflow connection. By embedding an acoustic path between the layers or creating an acoustic path on the surface of a flex or PCB assembly, the microphone can be reflowed onto the manifold assembly.
1. A microphone assembly for a hearing assistance device, comprising:
a microphone having a planar surface with an acoustic inlet port;
a printed circuit board (PCB) having a printed trace connecting two points on an edge of the PCB;
a solder mask having a cut-out with a border that matches the shape of the printed trace;
wherein the microphone is stacked on the printed circuit board with the solder mask interposed therebetween; and,
wherein an acoustic inlet manifold continuous with the acoustic inlet port is created between the microphone, the cut-out of the solder mask, and the printed trace.
2. The microphone assembly of claim 1 wherein the cut-out and printed trace are U-shaped.
3. The microphone assembly of claim 1 wherein the cut-out and printed trace are rectangularly shaped.
4. The microphone assembly of claim 1 wherein the planar surface has solder pads on the same side as the acoustic inlet port.
5. A method for constructing a microphone assembly, comprising:
disposing a microphone having a planar surface with an acoustic inlet port on a printed circuit board (PCB);
wherein the PCB has a printed trace connecting two points on an edge of the PCB;
interposing a solder mask between the PCB and the microphone, the solder mask having a cut-out with a border that matches the shape of the printed trace;
wherein an acoustic inlet manifold continuous with the acoustic inlet port is created between the microphone, the cut-out of the solder mask, and the printed trace.
6. The method of claim 5 wherein the cut-out and printed trace are U-shaped.
7. The method of claim 5 wherein the cut-out and printed trace are rectangularly shaped.
8. The method of claim 5 wherein the planar surface has solder pads on the same side as the acoustic inlet port.