US 12,219,321 B2
Microelectromechanical systems sensor with stabilization circuit
Mark Niederberger, Einsiedeln (CH)
Assigned to Knowles Electronics, LLC, Itasca, IL (US)
Filed by Knowles Electronics, LLC, Itasca, IL (US)
Filed on Dec. 22, 2022, as Appl. No. 18/087,327.
Prior Publication US 2024/0214747 A1, Jun. 27, 2024
Int. Cl. H04R 19/04 (2006.01); H03F 3/183 (2006.01)
CPC H04R 19/04 (2013.01) [H03F 3/183 (2013.01); H03F 2200/03 (2013.01); H04R 2201/003 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A microelectromechanical systems (MEMS) sensor comprising:
a housing comprising electrical contacts disposed on an exterior of the housing;
a capacitive MEMS motor disposed in the housing; and
an electrical circuit disposed in the housing and electrically coupled to the electrical contacts, the electrical circuit comprising:
a bias voltage source having an output coupled to an input of the MEMS motor;
an amplifier including an amplifier input stage having an input, coupled to an output of the MEMS motor, the amplifier input stage having a negative input resistance, where a sum of a series resistance of the MEMS motor at the input and the negative input resistance is less than zero, and wherein application of a signal from the output of the MEMS motor to the input of the amplifier input stage produces a negative real part of input current; and
a stabilization circuit having an output coupled to the input of the amplifier input stage, where the stabilization circuit injects a compensation current at the input of the amplifier input stage that offsets at least a portion of the negative real part of input current.