Modular Power Converter

Abstract

A power converter comprises an input connection to a single power source, an output connection to a single coil, and a daisy-chain connection coupled to the output connection and configured to enable coupling of at least one additional daisy-chained power converter and at least one respective additional power source to the single coil. The power converter further comprises a power integrator coupled between the input connection and the output connection and adapted for summing power from the power sources into a single voltage on the single coil and a time multiplexer coupled to the power integrator configured to control power integration.

1 . A power converter comprising: 
 an input connection to a single power source;    an output connection to a single coil;    a daisy-chain connection coupled to the output connection and configured to enable coupling of at least one additional daisy-chained power converter and at least one respective additional power source to the single coil;    a power integrator coupled between the input connection and the output connection and adapted for summing power from the power sources into a single voltage on the single coil; and    a time multiplexer coupled to the power integrator configured to control power integration.    
   
   
       2 . The power converter according to  claim 1  further comprising: 
 the power integrator comprising a pulse width modulation circuit;    the time multiplexer comprising an oscillator, a divide-by-N circuit coupled to the oscillator whereby N corresponds to the number of daisy-chained power converters, a detect clock configured to detect a clock signal from a daisy-chained power converter, and a multiplexer coupled to receive input signals from the divide-by-N circuit and the detect clock and coupled to drive the pulse width modulation circuit;    the single coil comprising a primary winding of a single flyback transformer; and    at least one optical isolator configured to isolate a secondary winding of the single flyback transformer.    
   
   
       3 . The power converter according to  claim 1  further comprising: 
 the power integrator comprising a pulse width modulation circuit;    the time multiplexer comprising an oscillator, a divide-by-N circuit coupled to the oscillator whereby N corresponds to the number of daisy-chained power converters, a detect clock configured to detect a clock signal from a daisy-chained power converter, and a multiplexer coupled to receive input signals from the divide-by-N circuit and the detect clock and coupled to drive the pulse width modulation circuit; and    the single coil comprising a buck inductor.    
   
   
       4 . The power converter according to  claim 1  further comprising: 
 the power integrator comprising a pulse width modulation circuit;    the time multiplexer comprising a delay-locked loop coupled to drive the pulse width modulation circuit, an oscillator, a detect clock configured to detect a clock signal from a daisy-chained power converter, a multiplexer coupled to receive input signals from the oscillator and the detect clock and coupled to drive the delay-locked loop;    the single coil comprising a primary winding of a single flyback transformer; and    at least one optical isolator configured to isolate a secondary winding of the single flyback transformer.    
   
   
       5 . The power converter according to  claim 1  further comprising: 
 the power integrator comprising a pulse width modulation circuit;    the time multiplexer comprising a delay-locked loop coupled to drive the pulse width modulation circuit, an oscillator, a detect clock configured to detect a clock signal from a daisy-chained power converter, a multiplexer coupled to receive input signals from the oscillator and the detect clock and coupled to drive the delay-locked loop; and    the single coil comprising a buck inductor.    
   
   
       6 . The power converter according to  claim 1  further comprising: 
 the power converter configured as a Power-over-Ethernet (PoE) integrated circuit;    the single power source configured as two wire pairs coupled to a Registered Jack (RJ)-45 connector;    a magnetic transformer coupled to the RJ-45 connector;    a Powered Device (PD) controller coupled to the single power source;    a diode bridge coupling the single power source to the PD controller; and    a Powered Device (PD) coupled to the single coil, powered by the single voltage.    
   
   
       7 . The power converter according to  claim 1  further comprising: 
 the power converter configured as a Power-over-Ethernet (PoE) integrated circuit;    the single power source configured as two wire pairs coupled to a Registered Jack (RJ)-45 connector;    a non-magnetic transformer and diode bridge integrated into the PoE integrated circuit and coupled to the RJ-45 connector;    a Powered Device (PD) controller coupled to the single power source;    a diode bridge coupling the single power source to the PD controller; and    a Powered Device (PD) coupled to the single coil, powered by the single voltage.    
   
   
       8 . The power converter according to  claim 1  further comprising: 
 the time multiplexer configured to perform adaptive power sharing for the power integrator based on power availability of the single power source and the additional power sources.    
   
   
       9 . The power converter according to  claim 1  further comprising: 
 a current sensor coupled to the power integrator; and    the time multiplexer configured to detect a current sensed by the current sensor that exceeds a predetermined maximum current and, in response to the current exceeding the maximum current, switching sourcing to one of the additional power sources.    
   
   
       10 . The power converter according to  claim 9  further comprising: 
 the time multiplexer configured to adaptively change the predetermined maximum current whereby power sourced by the single power source and the additional power sources is adaptively managed.    
   
   
       11 . The power converter according to  claim 1  further comprising: 
 the single power source and the additional power sources are selected from among two-wire pair sources and auxiliary sources.    
   
   
       12 . The power converter according to  claim 1  further comprising: 
 a Powered Device (PD) coupled to the single coil, powered by the single voltage;    the input connection coupled to a Power Sourcing Equipment (PSE); and    a controller configured to communicate detection, classification, and operational information between the Power Sourcing Equipment (PSE) and the Powered Device (PD) for accommodating a power consumption classification of the PD and identifying characteristics of the single power source and/or the additional power sources for sharing power adaptively by the time multiplexer.    
   
   
       13 . The power converter according to  claim 12  further comprising: 
 the controller configured to communicate detection, classification, and operational information independently for each power source of the single power source and the additional power sources and for current power consumption demand of the Powered Device (PD) for identifying characteristics of the power sources.    
   
   
       14 . The power converter according to  claim 1  further comprising: 
 the power converter operative in a single integrated circuit chip configuration whereby the single power source supplies the output connection to the single coil; and    the power converter operative in combination with a plurality of single integrated circuit chip in a daisy chain configuration as additional power sources become available, whereby time multiplexers for the plurality of power converters schedule power source control with the output connections coupled in parallel to the single coil.    
   
   
       15 . A Power-over-Ethernet (PoE) system comprising: 
 at least one modular power converter configured for coupling between a respective at least one power source and a single coil of a Powered Device (PD) in a daisy-chain arrangement whereby output connections of the at least one modular power converter are coupled in parallel to the single coil, the individual modular power converters comprising a power integrator and a time multiplexed scheduler coupled to the power integrator and configured to drive multiple power integrators for multiple modular power converters to integrate power from corresponding multiple sources into a single voltage on the single coil.    
   
   
       16 . The system according to  claim 15  wherein the at least one modular power converter further comprises: 
 the power converter configured as a Power-over-Ethernet (PoE) integrated circuit;    a single power source configured as two wire pairs coupled to a Registered Jack (RJ)-45 connector;    a magnetic transformer coupled to the RJ-45 connector;    a Powered Device (PD) controller coupled to the single power source; and    a diode bridge coupling the single power source to the PD controller.    
   
   
       17 . The system according to  claim 15  wherein the at least one modular power converter further comprises: 
 the power converter configured as a Power-over-Ethernet (PoE) integrated circuit;    the single power source configured as two wire pairs coupled to a Registered Jack (RJ)-45 connector;    a non-magnetic transformer and diode bridge integrated into the PoE integrated circuit and coupled to the RJ-45 connectors;    a Powered Device (PD) controller coupled to the single power source; and    a diode bridge coupling the single power source to the PD controller.    
   
   
       18 . The system according to  claim 15  further comprising: 
 the time multiplexed scheduler configured to perform adaptive power sharing for the power integrator based on power availability of the at least one power source.    
   
   
       19 . The system according to  claim 15  wherein the at least one modular power converter further comprises: 
 a current sensor coupled to the power integrator; and    the time multiplexed scheduler configured to detect a current sensed by the current sensor that exceeds a predetermined maximum current and, in response to the current exceeding the maximum current, switching sourcing of the at least one power source.    
   
   
       20 . The system according to  claim 19  further comprising: 
 the time multiplexed scheduler configured to adaptively change the predetermined maximum current whereby power sourced by the at least one power source is adaptively managed.    
   
   
       21 . The system according to  claim 15  further comprising: 
 the at least one power source is selected from among two-wire pair sources and auxiliary sources.    
   
   
       22 . The power converter according to  claim 15  further comprising: 
 a Powered Device (PD) coupled to the single coil, powered by the single voltage;    the at least one power source comprising at least one Power Sourcing Equipment (PSE); and    a controller configured to communicate detection, classification, and operational information between the at least one Power Sourcing Equipment (PSE) and the Powered Device (PD) for accommodating a power consumption classification of the PD and identifying characteristics of the at least one power source for sharing power adaptively by the time multiplexed scheduler.    
   
   
       23 . The power converter according to  claim 22  further comprising: 
 the controller configured to communicate detection, classification, and operational information independently for each power source of the single power source and the additional power sources and for current power consumption demand of the Powered Device (PD) for identifying characteristics of the power sources.    
   
   
       24 . The system according to  claim 15  further comprising: 
 the individual modular power converters operative in a single integrated circuit chip configuration whereby a single power source supplies the output connection to the single coil; and    a plurality of the modular power converters operative in combination in a daisy chain configuration as additional power sources become available, whereby time multiplexed schedulers for the plurality of modular power converters schedule power source control with the output connections coupled in parallel to the single coil.    
   
   
       25 . A system according to  claim 15  further comprising: 
 the single coil is selected from a primary winding of a single flyback transformer or a buck inductor;    the power integrator is selected from a group consisting of a Pulse Width Modulator (PWM), a forward bridge, a half bridge, a Pulse Frequency Modulator (PFM), and a Pulse Amplitude Modulator (PAM); and    a time multiplexed scheduler control element selected from a group consisting of a divide-by-N circuit and a Delay-Locked Loop (DLL).    
   
   
       26 . A method for power conversion in a network device comprising: 
 integrating power from a plurality of sources into a single voltage;    driving power integration according to time multiplexed scheduling; and    applying the integrated power onto a single winding of a flyback transformer or buck inductor.    
   
   
       27 . The method according to  claim 26  further comprising: 
 converting power in a Power-over-Ethernet (PoE) configuration; and    integrating power from at least two sources selected from two-wire pair sources and auxiliary sources.    
   
   
       28 . The method according to  claim 26  further comprising: 
 determining power available among the plurality of sources; and    adaptively sharing power based on the determined power availability.    
   
   
       29 . The method according to  claim 26  further comprising: 
 measuring current associated with the power sources;    determining when the measured current exceeds a predetermined current limit; and    adaptively switching power sourcing when the current limit is exceeded.    
   
   
       30 . The method according to  claim 27  further comprising: 
 adaptively changing current limits for the power source plurality; and    adaptively managing power sourced among the power source plurality.