Acoustic limiter for micro-electrical-mechanical systems (mems) microphones and other devices

A micro-electrical-mechanical system (MEMS) microphone with acoustic limiter, comprising:

• an acoustic limiter, comprising:
• a first housing having a first air passage operative as an acoustic input port;
• a second housing having a second air passage operative as an acoustic output port and having a rigid structure within the second air passage;
• and
• a flexible membrane, disposed between the first housing and the second housing, the flexible membrane having a first side, a second side opposite the first side, and at least one opening through the flexible membrane from the first side to the second side, the first side of the flexible membrane disposed at a first end of the first air passage, the second side of the flexible membrane disposed at a first end of the second air passage,
• wherein the flexible membrane is operative to flex in response to acoustic pressure within the first air passage, and, in response to acoustic pressure that is higher than a predetermined threshold value, the flexible membrane is operative to flex a distance into the second housing such that the rigid structure completely or partially blocks the at least one opening through the flexible membrane and limits airflow speed into the second air passage, which limits the acoustic pressure within the second air passage;
• and
• a MEMS microphone element, acoustically coupled to the second air passage, wherein the acoustic limiter limits the acoustic pressure to which the MEMS microphone element is subjected.

A method for fabricating an acoustic limiter, the method comprising:

• providing a first housing having a first air passage;
• providing a second housing having a second air passage and a rigid structure within the second air passage;
• and
• providing a flexible membrane, disposed between the first housing and the second housing, the flexible membrane having a first side, a second side opposite the first side, and at least one opening through the flexible membrane from the first side to the second side, wherein the flexible membrane is operative to flex in response to acoustic pressure within the first air passage, and, in response to acoustic pressure that is higher than a predetermined threshold value, the flexible membrane is operative to flex a distance into the second housing such that the rigid structure completely or partially blocks at least one opening through the flexible membrane and limits airflow speed into the second air passage, which limits the acoustic pressure within the second air passage.