Power adapter having a speaker for an electronic device

Abstract

A power adapter for an electronic device, such as a notebook computer, includes a speaker to generate low audio frequencies, such as below 150 Hz. The speaker can be mounted in a variety of arrangements, i.e. closed-box, bass-reflex, or a more intricate shape which adds resonance (poles and zeros) to the acoustic filtering properties of the enclosure. An exemplary bass-reflex mounting includes a driver with resonance at 140 Hz, a chamber size of 7.74 in 3 and a port determined by Thiele-Small equations. This gives a low frequency response beginning at 70 Hz. This low frequency component is combined in free space with the higher frequency components emanating from the portable electronic device's internal speaker(s). The audio signal connection can be made when the AC adapter is connected to the notebook computer by using two additional wires in the power cord. Since users generally carry their AC adapters with them, they can enjoy full harmonic sound without taking anything extra along. Alternatively, the AC adapter and electronic device can contain additional circuitry to provide wireless paths for either the power distribution path or audio interface or both.

What is claimed is:  
     
         1 . A power adapter, comprising: 
 a first speaker coupled to an audio inlet; and    means for converting energy from a mains receptacle to a power outlet.    
     
     
         2 . The power adapter of    claim 1   , further comprising: 
 a cavity that encloses said first speaker to form a resonant chamber.    
     
     
         3 . The power adapter of    claim 2   , further comprising: 
 a vented port in said cavity.    
     
     
         4 . The power adapter of    claim 1   , further comprising: 
 a second speaker coupled to said audio inlet.    
     
     
         5 . The power adapter of    claim 4   , further comprising: 
 a cavity the encloses said first speaker and said second speaker to form a resonant chamber.    
     
     
         6 . The power adapter of    claim 5   , further comprising: 
 a vented portion said cavity.    
     
     
         7 . The power adapter of    claim 1   , wherein: 
 said means for converting energy comprises an AC to DC switching power supply.    
     
     
         8 . The power adapter of    claim 1   , wherein: 
 said means for converting energy comprises an AC to AC inductive transformer.    
     
     
         9 . An electronic system with enhanced audio, comprising: 
 an electronic device, comprising; 
 an audio outlet;  
 a power inlet;  
   a power adapter external to said electronic device, comprising; 
 a mains receptacle;  
 a power outlet;  
 an audio inlet;  
 a speaker connected to said audio inlet;  
 means for converting energy from said mains receptacle to said power outlet;  
   means for coupling said power outlet to said power inlet; and    means for interfacing said audio outlet to said audio inlet.    
     
     
         10 . The electronic system of    claim 9   , wherein: 
 said electronic device is a portable computer.    
     
     
         11 . The electronic system of    claim 9   , wherein: 
 said electronic device is a portable television.    
     
     
         12 . The electronic system of    claim 9   , wherein: 
 said means for coupling comprises a plurality of wires.    
     
     
         13 . The electronic system of    claim 9   , wherein: 
 said means for coupling comprises wireless electromagnetic coupling.    
     
     
         14 . The electronic system of    claim 9   , wherein: 
 said means for interfacing comprises a plurality of wires.    
     
     
         15 . The electronic system of    claim 9   , wherein: 
 said means for interfacing comprises an infrared transmitter and an infrared receiver.    
     
     
         16 . The electronic system of    claim 9   , wherein: 
 said means for converting energy comprises an AC to DC switching power supply.    
     
     
         17 . The electronic system of    claim 9   , wherein: 
 said means for converting energy comprises an AC to AC inductive transformer.    
     
     
         18 . An electronic system with enhanced audio, comprising: 
 an electronic device, comprising; 
 a power inlet;  
 a power signal coupled with said power inlet;  
 an audio signal;  
 a delta-sigma modulator having said audio signal as an input and a modulated signal as an output;  
 means for superimposing said modulated signal onto said power signal;  
   a power adapter external to said electronic device, comprising; 
 a mains receptacle;  
 a power outlet;  
 means for converting energy from said mains receptacle to said power outlet;  
 a superimposed signal received from said power outlet;  
 a high pass filter having said superimposed signal as an input and a filtered digital signal as an output;  
 a discriminator having said filtered digital signal as an input and a recovered modulated signal as an output;  
 a low pass filter having said recovered modulated signal as an input and a recovered audio signal as an output;  
 a speaker driven by said recovered audio signal; and  
   means for coupling said power outlet to said power inlet.    
     
     
         19 . The electronic system of    claim 18   , wherein: 
 said means for coupling comprises a plurality of wires.    
     
     
         20 . The electronic system of    claim 18   , wherein: 
 said means for coupling comprises wireless electromagnetic coupling.    
     
     
         21 . The electronic system of    claim 18   , wherein said power adapter further comprises: 
 a cavity that encloses said speakers to form a resonant chamber.    
     
     
         22 . The electronic system of    claim 21   , wherein said power adapter further comprises: 
 a vented port in said cavity.