Efficient use of energy in a switching power converter

Abstract

A system may include a power converter having a maximum allowable input power drawn from a power source, an energy storage element coupled to an output of the power converter at a top plate of the energy storage element, wherein the energy storage element is configured to store excess energy, and control circuity configured to, when an input power of the power converter exceeds the maximum allowable input power, cause excess energy stored in the energy storage element to be consumed by circuitry coupled to the output of the power converter, and in order to maintain positive voltage headroom for the circuitry coupled to the output of the power converter, selectively couple a bottom plate of the energy storage element to the power source such that excess energy stored by the circuitry coupled to the output of the power converter is consumed from the energy storage device when the input power of the power converter exceeds the maximum allowable input power.

1 .- 5 . (canceled) 
     
     
         6 . A system comprising:
 a power converter configured to generate a first supply voltage at a first supply output; and   a second supply output configured to generate a second supply voltage lower than the first supply voltage, wherein the second supply voltage tracks an envelope of an output signal generated by an amplifier coupled to the power supply.   
     
     
         7 . The system of  claim 6 , wherein the amplifier is configured to select between the first supply voltage and the second supply voltage as a supply voltage to the amplifier. 
     
     
         8 . A system comprising:
 a power supply comprising:
 a power converter configured to generate a first supply voltage at a first supply output of the power supply; and 
 a second supply output configured to generate a second supply voltage lower than the first supply voltage; and 
   an amplifier coupled to the power supply and configured to select between the first supply voltage and the second supply voltage as a supply voltage to the amplifier.   
     
     
         9 . The system of  claim 8 , wherein the second supply voltage tracks an envelope of an output signal generated by the amplifier. 
     
     
         10 . The system of  claim 8 , wherein the second supply voltage is provided by a fixed voltage supply external to a switched mode power converter. 
     
     
         11 . The system of  claim 8 , wherein the second supply voltage is provided by a power source coupled to an input of a power supply. 
     
     
         12 . The system of  claim 11 , wherein the power source is a battery. 
     
     
         13 . A system comprising:
 a power converter configured to generate a first supply voltage at a first supply output of the power supply, the power converter having a maximum allowable input power drawn from a power source;   an energy storage element coupled to an output of the power converter at a top plate of the energy storage element, wherein the energy storage element is configured to store excess energy; and   a second supply output configured to generate a second supply voltage lower than the first supply voltage, wherein:
 the second supply voltage tracks an envelope of an output signal generated by an amplifier coupled to the power supply when the amplifier consumes power from the second supply output; and 
 the second supply voltage regulates a voltage at a bottom plate of the energy storage element when the amplifier consumes power from the first supply output. 
   
     
     
         14 .- 18 . (canceled) 
     
     
         19 . A method comprising:
 generating a first supply voltage at a first supply output with a power converter; and   generating a second supply voltage lower than the first supply voltage with a second supply output, wherein the second supply voltage tracks an envelope of an output signal generated by an amplifier coupled to the power supply.   
     
     
         20 . The method of  claim 19 , further comprising selecting, by the amplifier, between the first supply voltage and the second supply voltage as a supply voltage to the amplifier. 
     
     
         21 . A method comprising:
 generating a first supply voltage of a power supply at a first supply output with a power converter;   generating a second supply voltage of the power supply lower than the first supply voltage with a second supply output; and   selecting, by an amplifier coupled to the power supply, between the first supply voltage and the second supply voltage as a supply voltage to the amplifier.   
     
     
         22 . The method of  claim 21 , further comprising tracking, by the second supply voltage, an envelope of an output signal generated by the amplifier. 
     
     
         23 . The method of  claim 21 , comprising supplying the second supply voltage from a fixed voltage supply external to the switched mode power converter. 
     
     
         24 . The method of  claim 21 , comprising supplying the second supply voltage from a power source coupled to an input of a power supply. 
     
     
         25 . The method of  claim 24 , wherein the power source is a battery. 
     
     
         26 . A method in a system having a power converter configured to generate a first supply voltage at a first supply output of a power supply, the power converter having a maximum allowable input power drawn from a power source, an energy storage element coupled to an output of the power converter at a top plate of the energy storage element, wherein the energy storage element is configured to store excess energy, and a second supply output configured to generate a second supply voltage lower than the first supply voltage, the method comprising:
 tracking, with the second supply voltage, an envelope of an output signal generated by an amplifier coupled to the power supply when the amplifier consumes power from the second supply output; and   regulating, with the second supply voltage, a voltage at a bottom plate of the energy storage element when the amplifier consumes power from the first supply output.