Patent application number | Description | Published |
20130021828 | INTEGRATED ON-TIME EXTENSION FOR NON-DISSIPATIVE BLEEDING IN A POWER SUPPLY - An example controller for a switched mode power supply includes a comparator, a drive logic, and an on-time extension block. The comparator has an output indicating whether the current through a switch of the power supply exceeds a zero-crossing current threshold. The drive logic is to generate a drive logic output signal in response to the current sense signal and in response to a feedback signal, where the drive logic output signal is representative of an on-time of the switch to regulate the output of the power supply. The on-time extension block is coupled to control switching of a switch and to extend the on-time until the output of the comparator indicates that the current sense signal reaches the zero-crossing current threshold or until the on-time of the switch reaches a zero-crossing time threshold. | 01-24-2013 |
20130027991 | METHOD AND APPARATUS TO CONTROL A POWER CONVERTER HAVING A LOW LOOP BANDWIDTH - An example controller includes a comparator coupled to receive a feedback signal representative of an output of the power converter. A counter is coupled to receive an output of the comparator and a feedback sampling signal. The counter is coupled to sample the output of the comparator in response to the feedback sampling signal. A state machine is coupled to receive a feedback time period signal. The state machine is coupled to control switching of the power converter according to one of a plurality of operating conditions in response to the counter and the feedback time period signal. A period of the feedback time period signal is substantially greater than a period of the feedback sampling signal. The state machine is coupled to be updated in response to the feedback time period signal. | 01-31-2013 |
20130070488 | Power Supply Circuit with a Control Terminal for Different Functional Modes of Operation - A method of operation for flyback power converter includes operating a controller of the flyback power converter in a regulation mode when a control signal is below a first threshold. The control signal is provided as an input to a terminal of the flyback power converter. When the control signal is below a second threshold and above the first threshold, the controller is operated in a limiting mode. The controller is operated in an external command mode when the control signal is below a third threshold and above the second threshold. Lastly, when the control signal is above the third threshold, the controller is operated in a protection mode. | 03-21-2013 |
20130241440 | PHASE ANGLE MEASUREMENT OF A DIMMING CIRCUIT FOR A SWITCHING POWER SUPPLY - An example switched mode power supply includes a timer, a threshold adjust circuitry, a comparator, and a control circuitry. The timer times a duration between crossings of a phase-dimmed signal across a first threshold. The threshold adjust circuitry adjusts a second threshold representative of a desired output of the switched mode power supply, where the second threshold is adjusted responsive to the timed duration between crossings. The comparator compares a feedback signal with the second threshold and generates a comparison result. The control circuitry controls switching of a power switch responsive to the comparison result to regulate the output of the switched mode power supply. | 09-19-2013 |
20130320882 | INTEGRATED ON-TIME EXTENSION FOR NON-DISSIPATIVE BLEEDING IN A POWER SUPPLY - An example controller for a switched mode power supply includes a zero crossing detector, drive logic, and a logic gate. The zero-crossing detector generates a zero-crossing signal indicating a zero-crossing condition in the power supply. The drive logic generates a drive logic output signal in response to the zero-crossing signal and in response to a feedback signal, where the drive logic output signal is representative of an on-time of a switch to regulate an output of the power supply. The logic gate is coupled to receive a first signal representative of a current through the switch and a second signal representative of a zero-crossing time threshold. The logic gate is further coupled to extend the on-time of the switch until current through the switch reaches a zero-crossing current threshold or until the on-time of the switch reaches the zero-crossing time threshold. | 12-05-2013 |
20130336019 | METHOD AND APPARATUS FOR DETERMINING ZERO-CROSSING OF AN AC INPUT VOLTAGE TO A POWER SUPPLY - An example controller for a power supply includes a first circuit and a drive signal generator. The first circuit receives a first signal representative of a switch current flowing through a switch of the power supply and then generates a second signal in response the switch current not reaching a current threshold within an amount of time. The second signal indicates when a dimming circuit at an input of the power supply is utilized. The drive signal generator generates a drive signal to control switching of the switch in response to the second signal, where energy is transferred across an energy transfer element of the power supply in response to the switching of the switch. | 12-19-2013 |
20140016377 | METHOD AND APPARATUS TO CONTROL A POWER CONVERTER HAVING A LOW LOOP BANDWIDTH - A controller for use in a power converter includes a comparator coupled to receive a signal representative of an output of the power converter. A counter is coupled to an output of the comparator to sample the output of the comparator a plurality of times within a period. A state machine is coupled to an output of the counter to control switching of the power converter according to one of a plurality of operating condition states in response to the output of the counter. The state machine is coupled to be updated at an end of the period. | 01-16-2014 |
20140132184 | Power Supply Circuit with a Control Terminal for Different Functional Modes of Operation - A method of operation for flyback power converter includes operating a controller of the flyback power converter in a regulation mode when a control signal is below a first threshold. The control signal is provided as an input to a terminal of the flyback power converter. When the control signal is below a second threshold and above the first threshold, the controller is operated in a limiting mode. The controller is operated in an external command mode when the control signal is below a third threshold and above the second threshold. Lastly, when the control signal is above the third threshold, the controller is operated in a protection mode. | 05-15-2014 |