Microphone assembly and method of manufacturing a microphone assembly
View Patent ↗A microphone assembly and a method for manufacturing a microphone assembly are disclosed. In an embodiment, the microphone assembly includes a MEMS dual backplate microphone configured to provide a differential output signal, an ASIC including a differential amplifier configured to receive the differential output signal and a control element configured to adjust at least one of a setting of the MEMS dual backplate microphone and a setting of the ASIC.
1. A microphone assembly comprising:
a MEMS dual backplate microphone configured to provide a differential output signal;
an ASIC comprising a differential amplifier configured to receive the differential output signal;
a memory element configured to store information concerning a setting of a parameter of the ASIC; and
a control element configured to adjust the setting of the parameter of the ASIC,
wherein the ASIC comprises a first damping capacitor and a second damping capacitor,
wherein the control element is configured to adjust at least one of a capacitance of the first damping capacitor or a capacitance of the second damping capacitor,
wherein a first signal path connects a first backplate of the MEMS dual backplate microphone with a first input of the differential amplifier and a second signal path connects a second backplate of the MEMS dual backplate microphone with a second input of the differential amplifier,
wherein the first damping capacitor is connected to the first signal path and to a reference potential, and
wherein the second damping capacitor is connected to the second signal path and to the reference potential.
2. The microphone assembly according to claim 1 , wherein the differential amplifier is configured to provide a balanced output signal, and wherein the control element is configured to adjust the setting such that a balancing of the balanced output signal is optimized.
3. The microphone assembly according to claim 1 , wherein the differential amplifier is configured to provide a balanced output signal consisting of two complementary signals, and wherein the control element is configured to adjust the setting such that clipping is reached simultaneously for the two complementary signals of the balanced output signal.
4. The microphone assembly according to claim 1 , wherein the MEMS dual backplate microphone comprises a membrane arranged between a first backplate and a second backplate, wherein the control element is configured to adjust a voltage applied to the membrane, and/or wherein the control element is configured to adjust a voltage applied to the first backplate and a voltage applied to the second backplate.
5. The microphone assembly according to claim 1 , wherein the control element is configured to adjust a gain setting of the differential amplifier.
6. The microphone assembly according to claim 1 , wherein the memory element is a non-volatile memory.
7. The microphone assembly according to claim 1 , wherein the memory element is a one time programming device.
8. A method for manufacturing a microphone assembly, wherein the microphone assembly comprises a MEMS dual backplate microphone configured to provide a differential output signal, an ASIC comprising a differential amplifier configured to receive the differential output signal, a memory element configured to store information concerning a setting of a parameter of the ASIC and a control element configured to adjust the setting of the parameter of the ASIC, wherein the ASIC comprises a first damping capacitor and a second damping capacitor, wherein the control element is configured to adjust at least one of a capacitance of the first damping capacitor or a capacitance of the second damping capacitor, wherein a first signal path connects a first backplate of the MEMS dual backplate microphone with a first input of the differential amplifier and a second signal path connects a second backplate of the MEMS dual backplate microphone with a second input of the differential amplifier, wherein the first damping capacitor is connected to the first signal path and to a reference potential, and wherein the second damping capacitor is connected to the second signal path and to the reference potential, the method comprising:
testing the microphone assembly;
determining the setting of the parameter of the ASIC; and
storing the setting in the memory element.
9. The method according to claim 8 , wherein the MEMS dual backplate microphone comprises a membrane arranged between a first backplate and a second backplate, wherein determining the setting comprises determining a setting of a voltage applied to the membrane, and/or wherein determining the setting comprises determining a setting of a voltage applied to the first backplate and a voltage applied to the second backplate.
10. The method according to claim 8 , wherein determining the setting comprises determining a gain setting of the differential amplifier.
11. The method according to claim 8 , wherein the differential amplifier is configured to provide a balanced output signal, and wherein the setting is defined as a setting wherein a balancing of the balanced output signal is optimized.
12. The method according to claim 8 , wherein the differential amplifier is configured to provide a balanced output signal consisting of two complementary signals, and wherein the setting is defined as a setting wherein clipping is reached simultaneously for the two complementary signals of the balanced output signal.
13. The microphone assembly according to claim 1 , wherein the control element is configured to adjust the setting of the ASIC according to the information stored in the memory element.
14. The method according to claim 8 , wherein the control element is configured to adjust the setting of the ASIC according to the information stored in the memory element.