Abstract: A switched mode power supply circuit includes a switching converter receiving an input voltage and generating an output voltage from the input voltage in accordance with a switching signal. A switching controller unit is configured to generate the switching signal in accordance with a control parameter set such that the output voltage matches a set-point.

Abstract: In accordance with an embodiment, a power conversion method includes operating a power converter circuit in one of a first operation and a second operation mode based on a feedback signal and a signal level of an output signal at an output. The power converter includes a transformer with a primary winding and a secondary winding, a first electronic switch connected in series with the primary winding, and a rectifier circuit connected between the secondary winding and the output and comprising a second electronic switch.

Abstract: In accordance with an embodiment, a method includes disabling a first electronic switch connected in series with a primary winding of a transformer in a power converter circuit if an auxiliary voltage across an auxiliary winding of the transformer is outside a predefined voltage range. The power converter circuit further includes a secondary winding of the transformer, and a rectifier circuit connected between the secondary winding and an output, where the rectifier circuit comprises a second electronic switch.

Abstract: In accordance with an embodiment, a method of controlling a switched-mode power supply includes operating the switched-mode power supply in a first operating mode by monitoring a feedback signal from an output of the power supply using a feedback interface circuit in a first configuration. The method further includes determining when the feedback signal crosses a first threshold in a first direction, and transitioning the switched-mode power from the first operating to a second operating mode by switching the feedback interface circuit from the first configuration to a second configuration.

Abstract: A method of cycle-by-cycle operation of a switched-mode power converter includes converting an input voltage at the primary side to an output voltage at the secondary side by switching a transistor connected to the primary side from an on-state to an off-state during the present cycle, detecting valleys in a voltage across the transistor in the off-state, determining which valley at which the transistor is to be switched from the off-state to the on-state in the next switching cycle, and determining a maximum peak current limit for the primary side above which the transistor is switched from the on-state to the off-state in the next switching cycle. The maximum peak current limit is determined as a function of the input voltage and the valley at which the transistor is to be switched from the off-state to the on-state in the next switching cycle. Forced valley switching techniques are also disclosed.

Abstract: In accordance with an embodiment, a method in a voltage converter includes, in each of successive drive cycles, switching on for an on-period a first electronic switch connected in series with a primary winding of a transformer. Before first electronic switch is switched on, the transformer is pre-magnetized for a pre-magnetizing period, where there is a first delay time between an end of the pre-magnetizing period and a beginning of the on-period.

Abstract: The time when a switch is turned on from the time of one voltage valley to the time of another voltage valley may be adjusted for controlling an average load current or average load voltage. In some examples, the adjustment is instantaneous, and in some examples, the adjustment is gradual. Both of these example techniques provide for high switching efficiency of the switch.

Abstract: In accordance with an embodiment, a method includes driving an electronic switch in a switched-mode power converter in successive drive cycles, wherein driving the switch in each of the drive cycles comprises switching on the electronic for an on-period and subsequently switching off the electronic switch for an off-period. The method further includes establishing the on-period based on a comparison of an on-time signal with an off-threshold, calculating the off-threshold based on an output signal of the switched-mode power converter and a compensation offset, and calculating the compensation offset in one drive cycle based on an estimated delay time, wherein the estimated delay time is calculated based on a measured delay time and an estimated delay time of a previous drive cycle.

Abstract: In various embodiments a method is provided for determining a demagnetization zero current time for a switched mode power supply having a transformer, a first side and a second side being galvanically separated from each other and a switched mode power supply controller, the method including: determining a first voltage being applied to one side of the transformer; determining a second voltage provided at the other side of the transformer; determining a time the first voltage is provided to a winding of the transformer; and determining, by a circuit located on the same side of the transformer as the switched mode power supply controller, the demagnetization zero current time using the determined first voltage, the determined second voltage and the determined time.

Abstract: A converter may include a transformer; a first circuit arrangement coupled to a first transformer side; a second circuit arrangement coupled to a second transformer side, wherein the second circuit arrangement is configured to provide an output voltage; a first coupler configured to provide information about the output voltage to the first circuit arrangement; wherein the first circuit arrangement is configured to determine a state of the secondary side based on the received information about the output voltage, and to generate a switch control signal dependent on the determined state; a switch circuit arranged on the second side; and a second coupler configured to provide a switch control signal from the first circuit arrangement to the switch circuit; wherein the switch circuit is coupled to the first circuit arrangement to provide a first circuit arrangement control signal to the first circuit arrangement depending on the switch control signal.

Abstract: A method of operating a power supply having a transformer, a transistor controlling the current through a primary side of the transformer, and a control unit for controlling the switching of the transistor to generate current pulses in the transformer, is suggested, the method comprising receiving a feedback signal, and exiting a burst mode and entering a normal mode based on the feedback signal in case the feedback signal exceeds a first threshold value or in case the feedback signal exceeds a second threshold value for at least a first amount of time and in case the feedback signal exceeds a third threshold value, wherein the third threshold value is larger than the second threshold value and the first threshold value is larger than the third threshold value.

Abstract: In accordance with an embodiment, a method includes driving an electronic switch in a switched-mode power converter in successive drive cycles, wherein driving the switch in each of the drive cycles comprises switching on the electronic for an on-period and subsequently switching off the electronic switch for an off-period, and measuring an operation parameter of the switched-mode power converter during the on-periods of the drive cycles, and storing the operation parameter measured in an on-period if a duration of the on-period met a predefined criteria. The method further includes forcing the on-period of a drive cycle to meet the predefined criteria if the operation parameter has not been stored for a predefined number of drive cycles, or for a pre-defined time duration.

Abstract: In accordance with an embodiment, a method in a voltage converter includes, in each of successive drive cycles, switching on for an on-period a first electronic switch connected in series with a primary winding of a transformer. Before first electronic switch is switched on, the transformer is pre-magnetized for a pre-magnetizing period, where there is a first delay time between an end of the pre-magnetizing period and a beginning of the on-period.

Abstract: A semiconductor arrangement includes a semiconductor body with a first active region, a second active region and an isolation region arranged between the first and the second active regions. At least one source region and at least one body region of a first transistor are integrated in the first active region. At least one source region and at least one body region of a second transistor are integrated in the second active region. Source and body regions of a third transistor are integrated in the second active region. The second transistor and the third transistor have a common source electrode. The first transistor, the second transistor and the third transistor have a common drain electrode.

Abstract: A method of operating a power supply having a transformer, a transistor controlling the current through a primary side of the transformer, and a control unit for controlling the switching of the transistor to generate current pulses in the transformer, is suggested, the method comprising receiving a feedback signal, and exiting a burst mode and entering a normal mode based on the feedback signal in case the feedback signal exceeds a first threshold value or in case the feedback signal exceeds a second threshold value for at least a first amount of time and in case the feedback signal exceeds a third threshold value, wherein the third threshold value is larger than the second threshold value and the first threshold value is larger than the third threshold value.

Abstract: A converter is suggested comprising a transformer providing a galvanic isolation between a primary side and a secondary side of the converter; at least one switching element; a converter control unit comprising a first pin for controlling the at least one switching element and a second pin for detecting a current signal in the at least one switching element during a first phase; and for detecting an output voltage signal of the secondary side of the converter and an information regarding a current in a secondary winding of the transformer during a second phase.

Abstract: In accordance with an embodiment, a method of operating a switched-mode power converter includes driving a switching element in successive drive cycles, in which the switching element is driven to switch on for an on-period and subsequently driven to switch off for an off-period; sampling a feedback signal two or more times during the drive cycles, where the feedback signal includes a signal representative of an operation parameter of the switched-mode power converter and noise. The method further includes filtering the sampled feedback signal to extract the signal representative of the operation parameter from the sampled feedback signal and controlling the switching element according to the filtered feedback signal.

Abstract: In accordance with an embodiment, a method includes driving an electronic switch in a switched-mode power converter in successive drive cycles, wherein driving the switch in each of the drive cycles comprises switching on the electronic for an on-period and subsequently switching off the electronic switch for an off-period. The method further includes establishing the on-period based on a comparison of an on-time signal with an off-threshold, calculating the off-threshold based on an output signal of the switched-mode power converter and a compensation offset, and calculating the compensation offset in one drive cycle based on an estimated delay time, wherein the estimated delay time is calculated based on a measured delay time and an estimated delay time of a previous drive cycle.

Abstract: In accordance with an embodiment, a method of controlling a switched-mode power supply includes operating the switched-mode power supply in a first operating mode by monitoring a feedback signal from an output of the power supply using a feedback interface circuit in a first configuration. The method further includes determining when the feedback signal crosses a first threshold in a first direction, and transitioning the switched-mode power from the first operating to a second operating mode by switching the feedback interface circuit from the first configuration to a second configuration.

Abstract: Techniques are described to adjust the time when a switch is turned on from the time of one voltage valley to the time of another voltage valley for controlling an average load current or average load voltage. In some examples, the adjustment is instantaneous, and in some examples, the adjustment is gradual. Both of these example techniques provide for high switching efficiency of the switch.