# US 10,771,904 B2 · Directional MEMS microphone with correction circuitry > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,771,904 B2 - Document ID: US10771904B2 - Status: Granted - Kind: B2 - Application number: 16/254,754 - Filed: 2019-01-23 - Published: 2019-07-25 - Granted: 2020-09-08 - Earliest claimed: 2018-01-24 - Assignees: Shure Acquisition Holdings, Inc. - Applicants: Shure Acquisition Holdings, Inc. - Inventors: Jordan Schultz - Web page: https://patentgrep.com/patent/US10771904B2 ## CPC - H04R 19/04: Microphones (H04R19/01 takes precedence) - H04R 1/04: Structural association of microphone with electric circuitry therefor (in electric hearing aids H04R25/00) - H04R 3/04: for correcting frequency response - H04R 3/06: of electrostatic transducers - H04R 19/005: {using semiconductor materials} - H04R 1/38: in which sound waves act upon both sides of a diaphragm and incorporating acoustic phase-shifting means, e.g. pressure-gradient microphone - H04R 2201/003: Mems transducers or their use - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) ## Abstract A microphone assembly is provided, comprising a transducer assembly including a first enclosure defining a first acoustic volume and a Micro-Electrical-Mechanical-System (“MEMS”) microphone transducer disposed within the first enclosure. The microphone assembly also includes a second enclosure disposed adjacent to the first enclosure and defining a second acoustic volume in acoustic communication with the first acoustic volume, the second enclosure including an acoustic resistance, wherein the first and second acoustic volumes, in cooperation with the acoustic resistance, create an acoustic delay for producing a directional polar pattern. Circuitry comprising a shelving filter configured to correct a portion of a frequency response of the MEMS microphone transducer is also provided. In some embodiments, the circuitry is embedded within the transducer assembly or at least included within the microphone assembly. In other embodiments, the circuitry is located on a cable that is electrically connected to a connection port of the microphone assembly. ## Claims ### Claim 1 A microphone assembly, comprising: a transducer assembly including a first enclosure defining a first acoustic volume and a Micro-Electrical-Mechanical-System (“MEMS”) microphone transducer disposed within the first enclosure such that the first acoustic volume surrounds a rear of the MEMS microphone transducer; a second enclosure disposed adjacent to the first enclosure and defining a second acoustic volume in acoustic communication with the first acoustic volume, the second enclosure including an acoustic resistance, wherein the first and second acoustic volumes, in cooperation with the acoustic resistance, create an acoustic delay for producing a directional polar pattern; and circuitry electrically coupled to the transducer assembly and comprising a shelving filter configured to correct a portion of a frequency response of the MEMS microphone transducer, so as to flatten the frequency response across all frequency values within a predetermined bandwidth. ### Claim 2 (depends on 1) The microphone assembly of claim 1, wherein the circuitry is mechanically attached to an exterior of the transducer assembly. ### Claim 3 (depends on 1) The microphone assembly of claim 1, wherein the circuitry is mechanically attached to an exterior of the second enclosure. ### Claim 4 (depends on 1) The microphone assembly of claim 1, wherein the directional polar pattern is a first order directional polar pattern. ### Claim 5 (depends on 1) The microphone assembly of claim 1, wherein the transducer assembly further includes an integrated circuit electrically coupled to the MEMS microphone transducer and disposed within the first enclosure, the circuitry being electrically connected to the integrated circuit of the transducer assembly. ### Claim 6 (depends on 1) The microphone assembly of claim 1, wherein the first enclosure includes an aperture to facilitate acoustic communication between the first acoustic volume and the second acoustic volume, the aperture being positioned adjacent to the MEMS microphone transducer. ### Claim 7 (depends on 6) The microphone assembly of claim 6, wherein the first enclosure includes a first sound inlet positioned adjacent to the MEMS microphone transducer, and the second enclosure includes a second sound inlet positioned a predetermined distance from the first sound inlet. ### Claim 8 (depends on 7) The microphone assembly of claim 7, wherein the predetermined distance is selected to create a pressure gradient across a diaphragm of the MEMS microphone transducer. ### Claim 9 (depends on 7) The microphone assembly of claim 7, wherein the acoustic resistance covers the second sound inlet. ### Claim 10 (depends on 1) The microphone assembly of claim 1, further comprising a connection port electrically coupled to the circuitry and configured to receive a cable for operatively coupling the transducer assembly to an external device. ### Claim 11 (depends on 1) The microphone assembly of claim 1, further comprising a substrate configured to support the transducer assembly. ### Claim 12 A microphone assembly, comprising: a transducer assembly including a Micro-Electrical-Mechanical-System (“MEMS”) microphone transducer, an integrated circuit electrically coupled to the MEMS microphone transducer, and a first enclosure defining a first acoustic volume and having disposed therein the integrated circuit and the MEMS microphone transducer, such that the first acoustic volume surrounds a rear of the MEMS microphone transducer; and a second enclosure disposed adjacent to the first enclosure and defining a second acoustic volume in acoustic communication with the first acoustic volume, the second enclosure including an acoustic resistance, and the first and second acoustic volumes creating an acoustic delay to produce a directional polar pattern, wherein the integrated circuit includes circuitry comprising a shelving filter configured to correct a portion of a frequency response of the MEMS microphone transducer, so as to flatten the frequency response across all frequency values within a predetermined bandwidth. ### Claim 13 (depends on 12) The microphone assembly of claim 12, wherein the integrated circuit is an Application Specific Integrated Circuit (ASIC). ### Claim 14 (depends on 12) The microphone assembly of claim 12, wherein the directional polar pattern is a first order directional polar pattern. ### Claim 15 (depends on 12) The microphone assembly of claim 12, wherein the second enclosure includes an aperture to facilitate acoustic communication between the first acoustic volume and the second acoustic volume, the aperture being positioned adjacent to the MEMS microphone transducer. ### Claim 16 (depends on 12) The microphone assembly of claim 12, wherein the first enclosure includes a first sound inlet positioned adjacent to the MEMS microphone transducer, and the second enclosure includes a second sound inlet positioned a predetermined distance from the first sound inlet. ### Claim 17 (depends on 16) The microphone assembly of claim 16, wherein the predetermined distance is selected to create a pressure gradient across a diaphragm of the MEMS microphone transducer. ### Claim 18 (depends on 16) The microphone assembly of claim 16, wherein the acoustic resistance covers the second sound inlet. ### Claim 19 (depends on 12) The microphone assembly of claim 12, further comprising a connection port electrically coupled to the integrated circuit and configured to receive a cable for operatively coupling the transducer assembly to an external device. ### Claim 20 (depends on 12) The microphone assembly of claim 12, further comprising a substrate configured to support the transducer assembly.