Mitigating an induced electrical signal from an appliance in a powered-off state

Abstract

An isolation unit may include input pins to receive an electrical signal induced by ambient sound waves incident on an appliance in a powered-off state, one or more first transformers, connected to the input pins, to electrically isolate the induced electrical, one or more second transformers, connected to the first transformers, to provide a common mode choke function on the induced electrical signal, one or more inductors, connected to the one or more second transformers, one or more resistors, connected to the one or more inductors, wherein the one or more inductors and the one or more resistors are configured to limit an amplitude of a current of the induced electrical signal, and output pins, connected to the one or more inductors, to receive a modified electrical signal from the one or more inductors to propagate the modified electrical signal to a downstream cable.

1 . An isolation unit, comprising:
 input pins configured to receive an induced electrical signal that is induced by ambient sound waves incident on an appliance when the appliance is in a powered-off state;   one or more first transformers, connected to at least a portion of the input pins, configured to electrically isolate the induced electrical signal;   one or more second transformers, connected to the one or more first transformers, configured to receive the induced electrical signal from the one or more first transformers, and further configured to provide a common mode choke function on the induced electrical signal;   and   output pins, connected to the one or more inductors, configured to receive a modified electrical signal from the one or more inductors, and further configured to propagate the modified electrical signal to a downstream cable.   
     
     
         2 . The isolation unit of  claim 1 , wherein the one or more first transformers are further configured to provide a frequency filtration function on one or more frequencies of the induced electrical signal. 
     
     
         3 . The isolation unit of  claim 1 , wherein the one or more second transformers are further configured to cancel one or more aspects of an amplitude of the induced electrical signal. 
     
     
         4 . The isolation unit of  claim 1 , wherein the modified electrical signal may not be transformed into an intelligible audio signal. 
     
     
         5 - 28 . (canceled) 
     
     
         29 . The isolation unit of  claim 1 , further comprising:
 one or more inductors connected to the one or more second transformers and one or more resistors connected to the one or more inductors, wherein the one or more inductors and the one or more resistors are configured to limit an amplitude of a current of the induced electrical signal.   
     
     
         30 . The isolation unit of  claim 1 , wherein the induced electrical signal is one of:
 triboelectrically induced by the ambient sound waves incident on the appliance; or   piezoelectrically induced by the ambient sound waves incident on the appliance.   
     
     
         31 . The isolation unit of  claim 1 , wherein the one or more first transformers are configured to attenuate one or more frequencies of the induced electrical signal in a range of from approximately 200 Hz to approximately 10,000 Hz. 
     
     
         32 . The isolation unit of  claim 1 , wherein the one or more first transformers are configured to attenuate one or more frequencies of the induced electrical signal in a range of from approximately 300 Hz to approximately 5,000 Hz. 
     
     
         33 . The isolation unit of  claim 1 , wherein the amplitude of current of the modified electrical signal is substantially below −120 dB. 
     
     
         34 . A method of modifying an induced electrical signal that is induced by ambient sound waves incident on an appliance, comprising:
 receiving, at input pins, the induced electrical signal when the appliance is in a powered-off state;   electrically isolating the induced electrical signal by one or more first transformers connected to at least a portion of the input pins;   receiving, at one or more second transformers connected to the one or more first transformers, the induced electrical signal;   providing, by the one or more second transformers, a common mode choke function on the induced electrical signal; and   outputting a modified electrical signal from the one or more inductors and propagating the modified electrical signal to a downstream cable via output pins connected to the one or more inductors.   
     
     
         35 . The method of  claim 34 , wherein electrically isolating the induced electrical signal by one or more first transformers connected to at least a portion of the input pins comprises:
 providing by the one or more first transformers a frequency filtration function on one or more frequencies of the induced electrical signal.   
     
     
         36 . The method of  claim 34 , wherein providing a common mode choke function on the induced electrical signal comprises:
 canceling the one or more second transformers one or more aspects of an amplitude of the induced electrical signal.   
     
     
         37 . The method of  claim 34 , wherein outputting the modified electrical signal comprises outputting an electrical signal that may not be transformed into an intelligible audio signal. 
     
     
         38 . The method of  claim 34 , further comprising:
 limiting, by one or more inductors connected to the one or more second transformers and one or more resistors connected to the one or more inductors, an amplitude of a current of the induced electrical signal.   
     
     
         39 . The method of  claim 34 , wherein receiving the induced electrical signal comprises receiving an electrical signal that is:
 triboelectrically induced by the ambient sound waves incident on the appliance; or   piezoelectrically induced by the ambient sound waves incident on the appliance.   
     
     
         40 . The method of  claim 34 , wherein electrically isolating the induced electrical signal by one or more first transformers connected to at least a portion of the input pins comprises:
 attenuating by the one or more first transformers one or more frequencies of the induced electrical signal in a range of from approximately 200 Hz to approximately 10,000 Hz.   
     
     
         41 . The method of  claim 34 , wherein electrically isolating the induced electrical signal by one or more first transformers connected to at least a portion of the input pins comprises:
 attenuating by the one or more first transformers one or more frequencies of the induced electrical signal in a range of from approximately 300 Hz to approximately 5,000 Hz.   
     
     
         42 . The method of  claim 34 , wherein outputting the modified electrical signal comprises outputting an electrical signal having an amplitude of current that is substantially below −120 dB.