Abstract: Systems and methods are provided for regulating a power converter. An example system controller includes: a first controller terminal configured to output a drive signal to a switch to affect a current flowing through a primary winding of a power converter, the drive signal being associated with a switching period corresponding to a switching frequency; and a second controller terminal configured to receive a feedback signal associated with an output voltage related to a secondary winding of the power converter. The first controller terminal is further configured to: output the drive signal to close the switch during the on-time period; and output the drive signal to open the switch during the off-time period. The system controller is configured to set the switching frequency to one or more frequency magnitudes, each of the one or more frequency magnitudes being smaller than or equal to an upper frequency limit.

Abstract: System and method for protecting a power converter. The system includes a first comparator configured to receive a first threshold signal and a first signal and to generate a first comparison signal. The first signal is associated with an input current for a power converter. Additionally, the system includes a second comparator configured to receive a second threshold signal and the first signal and to generate a second comparison signal. The second threshold signal is different from the first threshold signal in magnitude. Moreover, the system includes a first detection component configured to receive at least the second comparison signal, detect the second comparison signal only if one or more predetermined conditions are satisfied, and generate a first detection signal based on at least information associated with the detected second comparison signal.

Abstract: Systems and methods are provided for voltage regulation of power conversion systems. An example system controller includes: a first sampling component configured to sample a sensing signal and determine a compensation signal based on at least in part on the sensing signal, the sensing signal being associated with a first current flowing through a primary winding of a power conversion system; a signal processing component configured to receive a feedback signal and the compensation signal and generate a first signal based at least in part on the feedback signal and the compensation signal, the feedback signal being associated with an auxiliary winding coupled with a secondary winding of the power conversion system; an error amplifier configured to receive the first signal and a reference signal and generate an amplified signal based at least in part on the first signal and the reference signal.

Abstract: System and method for regulating a power conversion system. For example, a system controller for regulating a power conversion system includes an amplifier, a variable-resistance component, a capacitor, and a modulation and drive component. The amplifier is configured to receive a reference signal and a feedback signal associated with an output signal of the power conversion system, the amplifier including an amplifier terminal. The variable-resistance component is associated with a first variable resistance value, the variable-resistance component including a first component terminal and a second component terminal, the first component terminal being coupled with the amplifier terminal. The capacitor includes a first capacitor terminal and a second capacitor terminal, the first capacitor terminal being coupled with the second component terminal. The modulation and drive component includes a first terminal and a second terminal, the first terminal being coupled with the amplifier terminal.

Abstract: System and method for providing at least an output current to one or more light emitting diodes. The system includes a control component configured to receive at least a demagnetization signal, a sensed signal and a reference signal and to generate a control signal based on at least information associated with the demagnetization signal, the sensed signal and the reference signal, and a logic and driving component configured to receive at least the control signal and output a drive signal to a switch based on at least information associated with the control signal. The switch is connected to a first diode terminal of a diode and a first inductor terminal of an inductor. The diode further includes a second diode terminal, and the inductor further includes a second inductor terminal.

Abstract: System and method for providing at least an output current to one or more light emitting diodes. The system includes a control component configured to receive at least a demagnetization signal, a sensed signal and a reference signal and to generate a control signal based on at least information associated with the demagnetization signal, the sensed signal and the reference signal, and a logic and driving component configured to receive at least the control signal and output a drive signal to a switch based on at least information associated with the control signal. The switch is connected to a first diode terminal of a diode and a first inductor terminal of an inductor. The diode further includes a second diode terminal, and the inductor further includes a second inductor terminal.

Abstract: System controller and method for regulating a power converter. For example, the system controller includes a first controller terminal and a second controller terminal. The system controller is configured to receive, at the first controller terminal, an input signal, generate a drive signal based at least in part on the input signal, and output, at the second controller terminal, the drive signal to a switch to affect a current associated with a secondary winding of the power converter. The system controller is further configured to detect a first duration of a demagnetization period associated with the secondary winding based at least in part on the input signal, determine a second duration of a time period for the drive signal based at least in part on the first duration, and keep the drive signal at a first logic level during the entire time period.

Abstract: System controller and method for a power converter. For example, a system controller for a power converter includes a logic controller configured to generate a modulation signal, and a driver configured to receive the modulation signal, generate a drive signal based at least in part on the modulation signal, and output the drive signal to a switch to affect a current flowing through an inductive winding for a power converter. Additionally, the system controller includes a voltage-to-voltage converter configured to receive a first voltage signal, the modulation signal, and a demagnetization signal, and to generate a second voltage signal based at least in part on the first voltage signal, the modulation signal, and the demagnetization signal.

Abstract: System and method for controlling one or more switches. The system includes a first converting circuit, a second converting circuit, and a signal processing component. The first converting circuit is configured to convert a first current and generate a first converted voltage signal based on at least information associated with the first current. The second converting circuit is configured to convert a second current and generate a second converted voltage signal based on at least information associated with the second current. The signal processing component is configured to receive the first converted voltage signal and the second converted voltage signal and generate an output signal based on at least information associated with the first converted voltage signal and the second converted voltage signal.

Abstract: Systems and methods for dimming control using TRIAC dimmers are provided. An example apparatus for a power conversion system includes: a process-and-drive component configured to receive an input signal and output a drive signal to a switch to affect a current that flows through a primary winding of a power conversion system. The input signal includes a first pulse associated with a first input period and a second pulse associated with a second input period. The drive signal is associated with a first modulation period for the first input period and a second modulation period for the second input period. The process-and-drive component is further configured to: determine the first modulation period for the first input period; change the drive signal between a first logic level and a second logic level at a modulation frequency during the first modulation period; determine the second modulation period for the second input period.

Abstract: System and method for regulating a power conversion system. An example system controller for regulating a power conversion system includes a signal generator and a driving component. The signal generator is configured to receive a feedback signal associated with an output signal of a power conversion system and a current sensing signal associated with a primary current flowing through a primary winding of the power conversion system and generate a modulation signal based on at least information associated with the feedback signal and the current sensing signal. The driving component is configured to receive the modulation signal and output a drive signal to a switch based on at least information associated with the modulation signal.

Abstract: System and method for regulating a power conversion system. An example system controller includes a signal processing component and a driving component. The signal processing component is configured to receive a feedback signal associated with an output signal of a power conversion system and generate a processed signal based on at least information associated with the feedback signal. The driving component is configured to generate a drive signal based on at least information associated with the processed signal and output the drive signal to a switch in order to affect a primary current flowing through a primary winding, the drive signal being associated with a demagnetization period corresponding to a demagnetization process of the power conversion system. The signal processing component is further configured to, sample and hold the feedback signal a plurality of times during the demagnetization period to generate a plurality of sampled and held signals.

Abstract: Systems and methods are provided for regulating a power conversion system. An example system controller includes a driving component and a detection component. The driving component is configured to output a driving signal to a switch associated with a first current flowing through a primary winding of a power conversion system, the switch including a first switch terminal related to a first voltage and a second switch terminal related to a second voltage, the driving signal being associated with a plurality of switching periods. The detection component is configured to receive an input signal associated with a difference between the first voltage and the second voltage, detect at least one valley of the input signal in magnitude during a detection period for the first switching period, and output a detection signal based on at least information associated with the input signal to affect the driving signal.

Abstract: Systems and methods are provided for amplifying multiple input signals to generate multiple output signals. An example system includes a first channel, a second channel, and a third channel. The first channel is configured to receive one or more first input signals, process information associated with the one or more first input signals and a first ramp signal, and generate one or more first output signals. The second channel is configured to receive one or more second input signals, process information associated with the one or more second input signals and a second ramp signal, and generate one or more second output signals. The first ramp signal corresponds to a first phase. The second ramp signal corresponds to a second phase. The first phase and the second phase are different.

Abstract: System and method for regulating a power conversion system. An example system controller for regulating a power conversion system includes a first controller terminal associated with a first controller voltage and coupled to a first transistor terminal of a first transistor, the first transistor further including a second transistor terminal and a third transistor terminal, the second transistor terminal being coupled to a primary winding of a power conversion system, a second controller terminal associated with a second controller voltage and coupled to the third transistor terminal, and a third controller terminal associated with a third controller voltage. The first controller voltage is equal to a sum of the third controller voltage and a first voltage difference. The second controller voltage is equal to a sum of the third controller voltage and a second voltage difference.

Abstract: Systems and methods are provided for voltage regulation of power conversion systems. An example system controller includes: a first sampling component configured to sample a sensing signal and determine a compensation signal based on at least in part on the sensing signal, the sensing signal being associated with a first current flowing through a primary winding of a power conversion system; a signal processing component configured to receive a feedback signal and the compensation signal and generate a first signal based at least in part on the feedback signal and the compensation signal, the feedback signal being associated with an auxiliary winding coupled with a secondary winding of the power conversion system; an error amplifier configured to receive the first signal and a reference signal and generate an amplified signal based at least in part on the first signal and the reference signal.

Abstract: Systems and methods are provided for amplifying multiple input signals to generate multiple output signals. An example system includes: a first channel configured to receive a first input signal and a second input signal and generate a first output signal and a second output signal based at least in part on the first input signal and the second input signal; and a second channel configured to receive a third input signal and a fourth input signal and generate a third output signal and a fourth output signal based at least in part on the third input signal and the fourth input signal. A first differential signal is equal to the first input signal minus the second input signal. A second differential signal is equal to the third input signal minus the fourth input signal. The first output signal corresponds to a first phase.

Abstract: System and method for protecting a power converter. A system includes a threshold generator configured to generate a threshold signal, and a first comparator configured to receive the threshold signal and a first signal and to generate a comparison signal. The first signal is associated with an input current for a power converter. Additionally, the system includes a pulse-width-modulation generator configured to receive the comparison signal and generate a modulation signal in response to the comparison signal, and a switch configured to receive the modulation signal and adjust the input current for the power converter. The threshold signal is associated with a threshold magnitude as a function of time. The threshold magnitude increases with time at a first slope during a first period, and the threshold magnitude increases with time at a second slope during a second period. The first slope and the second slope are different.

Abstract: System and method for regulating a power converter. A system for regulating a power converter includes a controller, a first switch, and a second switch. The controller is configured to generate a first switching signal and a second switching signal. The first switch is configured to receive the first switching signal, the first switch being coupled to an auxiliary winding of the power converter further including a primary winding and a secondary winding. The second switch is configured to receive the second switching signal and coupled to the primary winding of the power converter. The controller is further configured to, change, at a first time, the second switching signal to open the second switch, maintain, from the first time to a second time, the first switching signal to keep the first switch open, and change, at the second time, the first switching signal to close the first switch.

Abstract: Systems and methods are provided for signal processing. An example error amplifier for processing a reference signal and an input signal associated with a current of a power conversion system includes a first operational amplifier, a second operational amplifier, a first transistor, a second transistor, a current mirror component, a switch, a first resistor and a second resistor. The first operational amplifier includes a first input terminal, a second input terminal and a first output terminal, the first input terminal being configured to receive a reference signal. The first transistor includes a first transistor terminal, a second transistor terminal and a third transistor terminal, the first transistor terminal being configured to receive a first amplified signal from the first output terminal, the third transistor terminal being coupled to the second input terminal.