Micro-electro-mechanical systems microphone with increased back volume

A Micro-Electro-Mechanical Systems (MEMS) microphone comprising:

• a housing comprising a cover mounted on a base comprising a first printed circuit board (PCB) facing a second PCB, the cover located on a side of the first PCB facing away from the second PCB;
• a first recess located in the base and comprising an aperture through the first PCB and a cavity in the second PCB;
• a second recess located in the base and at least partially defined by a cavity in the first PCB;
• an internal electrical interface located in the housing and on a side of the first PCB facing the second PCB;
• an external electrical interface located on a side of the base facing an exterior of the housing, the external electrical interface electrically connected to the internal electrical interface;
• an Integrated Circuit (IC) mounted on the inner side of the cover and electrically connected to the internal electrical interface via a conductor extending through the aperture of the first recess and into the cavity of the first recess;
• and
• a MEMS transducer located in the housing and mounted on an inner side of the cover over a sound port of the cover, the MEMS transducer electrically connected to the IC, the MEMS transducer comprising a diaphragm that separates an interior of the housing into a front volume and a back volume, the front volume located between the diaphragm and the sound port, and the back volume located between the diaphragm and the base, wherein the first recess and the second recess constitute a portion of the back volume.

A Micro-Electro-Mechanical Systems (MEMS) microphone comprising:

• a housing comprising a cover mounted on a base comprising a first printed circuit board (PCB) facing a second PCB, the cover located on a side of the first PCB facing away from the second PCB;
• a first recess located in the base and comprising an aperture through the first PCB and a cavity in the second PCB;
• an internal electrical interface located in the housing and on a side of the first PCB facing the second PCB;
• an external electrical interface located on a side of the base facing an exterior of the housing, the external electrical interface electrically connected to the internal electrical interface;
• an Integrated Circuit (IC) mounted on the inner side of the cover and electrically connected to the internal electrical interface via a conductor extending through the aperture of the first recess and into the cavity of the first recess;
• and
• a MEMS transducer located in the housing and mounted on an inner side of the cover over a sound port of the cover, the MEMS transducer electrically connected to the IC, the MEMS transducer comprising a diaphragm that separates an interior of the housing into a front volume and a back volume, the front volume located between the diaphragm and the sound port, and the back volume located between the diaphragm and the base, wherein the first recess and the second recess constitute a portion of the back volume.