Patent ID: 9521493
Filing Date: 2016-12-13
CPC Classification: H04R

Claim Text:
1. A hearing aid, comprising: a transducer that stimulates the anatomy of a patient; and an amplifier electrically connected to the transducer; wherein the hearing aid has an operational mode in which the transducer stimulates the anatomy of the patient in response to ambient sound from around the patient; wherein the hearing aid has a test mode at a predetermined test frequency; wherein in the test mode: the amplifier receives a periodic input signal at the test frequency; the amplifier produces a primary output signal electrically connected to the transducer; the primary output signal is periodic at the test frequency; the primary output signal has a predetermined peak primary output current; the primary output signal has a periodic primary output voltage flowing through the transducer; the amplifier produces a secondary output signal that is a scaled version of the primary output signal; a voltage is recorded from one of the primary and secondary output signals; a current is recorded from the other of the primary and secondary output signals; and an impedance of the transducer at the test frequency is determined from the recorded voltage and the recorded current.