Microphone module with sound pipe

Abstract

A microphone module has a substrate with an aperture to allow sound waves to pass through the substrate, a lid mounted to the substrate to define a first interior volume, a microphone mounted to the substrate within the first interior volume, and a housing coupled to the substrate and covering the aperture. The housing forms a second interior volume and includes an acoustic port configured to allow sound to enter the second interior volume. The module further includes a pipe extending from the acoustic port in the housing, and at least one exterior interface pad outside of the second interior volume. The pipe has an open end to receive sound waves and direct them toward the acoustic port in the housing. Moreover, the at least one exterior interface pad electrically couples to the microphone.

What is claimed is: 
     
         1 . A microphone module comprising:
 a substrate having a first side, and a second side opposite the first side, the substrate having an aperture extending from the first side to the second side to allow sound waves to pass through the substrate;   a lid mounted to the first side, the first side and lid defining a first interior volume, the aperture configured to allow sound to enter the first interior volume;   a microphone mounted to the first side and within the first interior volume;   a sound pipe having an open end to receive sound waves and direct the sound waves toward the aperture; and   at least one exterior interface pad on the second side and electrically coupled to the microphone.   
     
     
         2 . The microphone module of  claim 1 , further including a housing including the sound pipe, the sound pipe having a pipe volume, the pipe volume forming most of a second interior volume, the sound pipe being mounted substantially flush against the second side of the substrate. 
     
     
         3 . The microphone module of  claim 2 , wherein the housing and at least a portion of the second side of the substrate comprise a pipe volume. 
     
     
         4 . The microphone module of  claim 3 , wherein the housing being coupled to the second side and covering the aperture, the housing and second side forming a second interior volume, the housing including an acoustic port configured to allow sound to enter the second interior volume, the housing covering no more than a portion of the second side of the substrate. 
     
     
         5 . The microphone module of  claim 1 , wherein the sound pipe is straight. 
     
     
         6 . The microphone module of  claim 1 , further including a bend configured to allow the sound pipe to run from the microphone module to a distal sound source. 
     
     
         7 . The microphone module of  claim 1 , further including a flange, the sound pipe extending from the flange, the flange resting substantially flush against the second side of the substrate. 
     
     
         8 . A microphone module comprising:
 a substrate having a first side, and a second side opposite the first side, the substrate having an aperture extending from the first side to the second side to allow sound waves to pass through the substrate, the substrate having a metalized portion;   a lid mounted to the first side, the first side and lid defining a first interior volume, the lid being formed from a conductive material, the lid being electrically connected to the metalized portion of the substrate to protect against electromagnetic interference;   a microphone mounted to the first side and within the first interior volume, the microphone being a MEMS microphone;   a circuit chip coupled with the first side of the substrate and being electrically connected with the microphone, the circuit chip being mounted within the first interior volume;   a sound pipe having an open end to receive sound waves and direct the sound waves toward the aperture; and   at least one exterior interface pad on the second side and outside of the second interior volume, the at least one exterior interface pad electrically coupled to the microphone, the at least one exterior interface pad being solderable.   
     
     
         9 . The microphone module of  claim 8 , further including a housing including the sound pipe, the sound pipe having a pipe volume, the pipe volume forming most of a second interior volume, the sound pipe being mounted substantially flush against the second side of the substrate. 
     
     
         10 . The microphone module of  claim 9 , wherein the housing and at least a portion of the second side of the substrate comprise a pipe volume. 
     
     
         11 . The microphone module of  claim 10 , wherein the housing is coupled to the second side and covering the aperture and including an acoustic port configured to allow sound to enter the pipe volume, the housing covering no more than a portion of the second side of the substrate. 
     
     
         12 . The microphone module of  claim 8 , wherein the sound pipe is straight. 
     
     
         13 . The microphone module of  claim 8 , further including a bend configured to allow the sound pipe to run from the microphone module to a distal sound source. 
     
     
         14 . The microphone module of  claim 8 , further including a flange, the sound pipe extending from the flange, the flange resting substantially flush against the second side of the substrate.