Circuit and method of direct duty cycle current sharing

A direct duty cycle current share controller, comprising:

• a detection circuit coupled to receive a feedback signal indicative of an absolute power transfer level and an output coupled to control the absolute power transfer level;
• and
• a regulation circuit having a first input coupled to receive a control signal indicative of a relative power transfer level and a second input coupled to receive the output of the detection circuit and an output coupled to control the absolute power transfer level in response to the relative power transfer level,
• wherein the detection circuit includes an amplifier having a first input coupled to receive the feedback signal, a second input coupled to receive a reference signal and an output coupled to the second input of the regulation circuit.

A direct duty cycle current share controller, comprising:

• a first detection circuit coupled to receive a signal indicative of absolute current drive;
• a second detection circuit coupled to receive a signal indicative of relative current drive and the output of the first detection circuit;
• and
• a control circuit having a first input coupled to receive the output of the second detection circuit and coupled to provide a control signal used to substantially equalize the absolute and relative current drive,
• wherein the first detection circuit includes an amplifier having a first input coupled to a current sense terminal, a second input coupled to receive a feedback signal and an output coupled to provide an amplified current sense signal.

A method of operating a direct duty cycle current share controller, comprising:

• providing an absolute power transfer operating point;
• monitoring a signal indicative of a relative power transfer operating point;
• and
• directly modifying the absolute power transfer operating point to substantially equal the relative power transfer operating point,
• wherein providing the absolute power transfer operating point includes comparing a feedback signal to a reference signal indicative of the absolute power transfer operating point.

A method of operating a direct duty cycle current share controller operating between first and second duty cycles, comprising:

• establishing an absolute power transfer level at a first duty cycle;
• and
• directly changing the first duty cycle to the second duty cycle to substantially equate the absolute power transfer level to a relative power transfer level, wherein directly changing the first duty cycle to the second duty cycle comprises;
• monitoring a relative power transfer level;
• generating an error signal representing a difference between the relative and the absolute power transfer levels;
• and
• overriding the first duty cycle with the second duty cycle generated in response to the error signal.