Magnetic Sensor for a Transducer

Abstract

A system and method for assisting listening wherein an integrated circuit selects one or more audio sources from among a plurality audio sources to be presented to a signal processing circuit. Selection of the audio source can be automatically executed in response to detection of an external magnetic field, such as from a telephone handset, or manually controlled by a user input.

1 . An assisted-listening device comprising: 
 two or more audio sources adapted to provide an audio signal;    a signal processing circuit adapted to process the audio signal provided by the audio sources; and    an integrated circuit disposed in one of the audio sources, the integrated circuit including a sensor and a magnetic field threshold comparator for detecting an external magnetic field presence and a magnetic field threshold, the magnetic field threshold comparator including an output;    wherein the magnetic field threshold comparator output being operably coupled to the signal processing circuit changes in response to the sensed external magnetic field.    
   
   
       2 . The assisted-listening device of  claim 1 , wherein the integrated circuit further comprises: 
 a gate including two or more audio source inputs, and an output, the gate being adapted to select one or more of the inputs in response to the sensed external magnetic field and the gate output being operably connected to the signal processing circuit.    
   
   
       3 . The assisted-listening device of  claim 2 , wherein the integrated circuit further comprises: 
 a magnetic field threshold value operably coupled to the magnetic field threshold comparator, the comparator operably coupled to the sensor and adapted to provide to the signal processing circuit one or more of the audio source inputs to the gate in response to the sensed external magnetic field and the magnetic field threshold value.    
   
   
       4 . The assisted-listening device of  claim 1 , wherein the integrated circuit further comprises: 
 a manual override for allowing one or more audio source signals to be presented to the signal processing circuit.    
   
   
       5 . The assisted-listening device of  claim 1 , wherein the sensor is selected from the group consisting of a lateral bipolar magnetotransistor (LBMT), a split-drain MAGFET, a Hall effect sensor, a microelectromechanical system (MEMS) device, and an active telecoil.  
   
   
       6 . The assisted-listening device of  claim 1 , wherein the sensor has a power consumption of substantially 100 μW or less.  
   
   
       7 . The assisted-listening device of  claim 1 , wherein one or more of the audio sources is an electroacoustic transducer, an electromagnetic transducer, or combination thereof.  
   
   
       8 . The assisted-listening device of  claim 7 , wherein the electroacoustic transducer is a microphone.  
   
   
       9 . The assisted-listening device of  claim 7 , wherein the electromagnetic transducer is a telecoil.  
   
   
       10 . The assisted listening device of  claim 3 , wherein the integrated circuit further comprises: 
 a signal shaping device operably coupled to the signal processing circuit.    
   
   
       11 . The assisted-listening device of  claim 10 , wherein the signal shaping device is selected from the group consisting of biasing, amplifying, filtering, and rectifying devices.  
   
   
       12 . A device comprising: 
 a transducer adapted to provide a signal; and    a sensor for detecting an external magnetic field presence is disposed in the transducer.    
   
   
       13 . The device of  claim 12 , further comprising: 
 a magnetic field threshold comparator and a magnetic field threshold value, the magnetic field threshold comparator being operably coupled to the sensor and the magnetic field threshold value; and    a gate adapted to provide an output signal in response to the sensor detecting the presence of the external magnetic field;    wherein the magnetic field threshold comparator, the magnetic field threshold value, and the gate are disposed in the transducer.    
   
   
       14 . The device of  claim 13 , further comprising: 
 a signal processing circuit operably coupled to an output of the gate.    
   
   
       15 . The device of  claim 13 , further comprising: 
 one or more additional transducers adapted to provide at least one signal, the gate being adapted to select one or more signals in response to the sensed external magnetic field.    
   
   
       16 . The device of  claim 15 , further comprising: 
 a signal processing circuit operably coupled to the output of the gate.    
   
   
       17 . The device of  claim 15 , further comprising: 
 a manual override for allowing one or more signals to be output from the gate.    
   
   
       18 . The device of  claim 16 , further comprising: 
 a manual override for allowing one or more signals to be presented to the signal processing circuit.    
   
   
       19 . The device of  claim 12 , wherein the sensor is selected from the group consisting of a lateral bipolar magnetotransistor (LBMT), a split-drain MAGFET, a Hall effect sensor, a microelectromechanical system (MEMS) device, and an active telecoil.  
   
   
       20 . The device of  claim 12 , wherein the sensor has a power consumption of substantially 100 μW or less.  
   
   
       21 . The device of  claim 12 , wherein the transducer is a microphone or a telecoil.  
   
   
       22 . The device of  claim 15 , wherein one or more of the transducers is a microphone, a telecoil, or combination thereof.