US Patent No. 10,461,647

METHOD AND APPARATUS FOR A CONTROL CIRCUIT WITH MULTIPLE OPERATING MODES


Patent No. 10,461,647
Issue Date October 29, 2019
Title Method And Apparatus For A Control Circuit With Multiple Operating Modes
Inventorship Giao Pham, Milpitas, CA (US)
Assignee Power Integrations, Inc., San Jose, CA (US)

Claim of US Patent No. 10,461,647

1. A controller for a power converter, comprising:an oscillator coupled to a switch of the power converter to determine a time at which the switch is turned on at a beginning of a switching cycle of the switch, wherein the oscillator includes a capacitor, a charging current source coupled to charge the capacitor, and a discharging current source coupled to discharge the capacitor, wherein a time period for the capacitor to charge and discharge between first and second voltage levels is a time period of the switching cycle of the switch; and
a duty cycle mode control circuit coupled to operate in a first duty control mode in response to a feedback signal representative of an output of the power converter being between a first feedback signal value and a second feedback signal value, wherein the duty cycle mode control circuit is coupled to operate in a second duty control mode in response to the feedback signal being between the second feedback signal value and a third feedback signal value, wherein the duty cycle mode control circuit is coupled to operate in a third duty control mode in response to the feedback signal being between the third feedback signal value and a fourth feedback signal value.