Power supply controller with minimum-sum multi-cycle modulation

A power supply controller configured to regulate the output of a power supply by enabling and disabling switching periods defined by an oscillator, the power supply controller comprising:

• an error signal generator coupled to generate an error signal in response to the feedback signal and a reference signal;
• and
• a multi-cycle modulation circuit coupled to respond to a disabled switching period by generating a skip mask signal that defines a skip mask of K switching periods during which
• the power supply is allowed to transition from the first or another disabled switching period to an enabled switching period and
• the power supply is prevented from transitioning from an enabled switching period to a disabled switching period.

A power supply regulation circuit for a switch mode power supply, the power supply regulation circuit comprising:

• a feedback circuit to generate a feedback signal representative of an output level at the output of the switch mode power supply;
• a comparator coupled to receive the feedback signal and a reference value signal and to output an error signal;
• an oscillator to define, at least at light loads, a fixed switching period;
• and
• a multi-cycle modulation circuit coupled to modulate enabling and disabling of switching of a switch of the switch mode power supply over multiple of the fixed switching periods defined by the oscillator, the multi-cycle modulation circuit to respond to a disabled switching period by defining a skip mask of K switching periods during which
• the power supply is allowed to transition from the first or another disabled switching period to an enabled switching period, and
• the power supply is prevented from transitioning from an enabled switching period to a disabled switching period.

A multi-cycle modulation circuit coupled to modulate enabling and disabling of switching of a switch of the switch mode power supply, wherein the multi-cycle modulation circuit comprises:

• an oscillator to define at least at light loads, a fixed switching period,
• wherein the multi-cycle modulation circuit is coupled to modulate enabling and disabling of the switch of the switch mode power supply over multiple of the fixed switch periods defined by the oscillator, and
• wherein the multi-cycle modulation circuit is coupled to respond to a disabled switching period by defining a skip mask of K switching periods during which the switch mode power supply is allowed to transition from the first or another disabled switching period to an enabled switching period and the switch mode power supply is prevented from transitioning from an enabled switching period of the switch to a disabled switching period of the switch,
• wherein the switch mode power supply is allowed to transition from the first or another disabled switching period to an enabled switching period, and
• wherein the switch mode power supply is prevented from transitioning from an enabled switching period to a disabling switching period.