Abstract: A circuit includes an electronic switch configured to be coupled intermediate a high-voltage node and low-voltage circuitry and configured to couple the low-voltage circuitry to the high-voltage node. A voltage-sensing node is configured to be coupled to the high-voltage node via a pull-up resistor. A further electronic switch can be switched to a conductive state to couple the voltage-sensing node and the control node of the electronic switch. A comparator compares a threshold with a voltage at the voltage-sensing node and causes the further electronic switch to switch on in response to the voltage at said voltage-sensing node reaching said threshold. A charge pump coupled to the current flow-path of the electronic switch is activated to the conductive state to pump electric charge from the current flow-path of the electronic switch to the control node of the electronic switch via the further electronic switch switched to the conductive state.

Abstract: A circuit includes an electronic switch configured to be coupled intermediate a high-voltage node and low-voltage circuitry and configured to couple the low-voltage circuitry to the high-voltage node. A voltage-sensing node is configured to be coupled to the high-voltage node via a pull-up resistor. A further electronic switch can be switched to a conductive state to couple the voltage-sensing node and the control node of the electronic switch. A comparator compares a threshold with a voltage at the voltage-sensing node and causes the further electronic switch to switch on in response to the voltage at said voltage-sensing node reaching said threshold. A charge pump coupled to the current flow-path of the electronic switch is activated to the conductive state to pump electric charge from the current flow-path of the electronic switch to the control node of the electronic switch via the further electronic switch switched to the conductive state.

Abstract: In an embodiment, a brown-out protection circuit includes: a monitoring terminal; a threshold generator supplying a threshold voltage; a comparator to compare a monitoring voltage at the monitoring terminal and the threshold voltage; and a logic module supplying an enable signal having a brown-in logic value and a brown-out logic value. When the enable signal is at the brown-out logic value, the logic module checks transition conditions, relating to a number of usable transitions of the monitoring voltage from lower to greater than the threshold voltage, and time conditions, relating to permanence of the monitoring voltage above the threshold voltage after a usable transition or in an aggregated manner after a plurality of consecutive usable transitions. The logic module sets the enable signal to the brown-in logic value when the transition conditions or the time conditions are met.

Abstract: A circuit includes an electronic switch configured to be coupled intermediate a high-voltage node and low-voltage circuitry and configured to couple the low-voltage circuitry to the high-voltage node. A voltage-sensing node is configured to be coupled to the high-voltage node via a pull-up resistor. A further electronic switch can be switched to a conductive state to couple the voltage-sensing node and the control node of the electronic switch. A comparator compares a threshold with a voltage at the voltage-sensing node and causes the further electronic switch to switch on in response to the voltage at said voltage-sensing node reaching said threshold. A charge pump coupled to the current flow-path of the electronic switch is activated to the conductive state to pump electric charge from the current flow-path of the electronic switch to the control node of the electronic switch via the further electronic switch switched to the conductive state.

Abstract: An embodiment PFC control circuit includes a first terminal providing a drive signal to an electronic switch of a boost converter, a second terminal receiving a feedback signal indicative of an output voltage generated by the boost converter, and a third terminal connected to a compensation network. An error amplifier generates a current as a function of the voltage at the second terminal and a reference voltage, wherein an output of the error amplifier is coupled to the third terminal. A driver circuit generates the drive signal as a function of the voltage at the third terminal, and selectively activates or deactivates the generation of the drive signal as a function of a burst mode enable signal. A detection circuit generates the burst mode enable signal as a function of the voltage at the second terminal.

Abstract: An embodiment PFC control circuit comprises a first terminal providing a drive signal to an electronic switch of a boost converter, a second terminal receiving a feedback signal indicative of an output voltage generated by the boost converter, and a third terminal connected to a compensation network. An error amplifier generates a current as a function of the voltage at the second terminal and a reference voltage, wherein an output of the error amplifier is coupled to the third terminal. A driver circuit generates the drive signal as a function of the voltage at the third terminal, and selectively activates or deactivates the generation of the drive signal as a function of a burst mode enable signal. A detection circuit generates the burst mode enable signal as a function of the voltage at the second terminal.

Abstract: In an embodiment, a brown-out protection circuit includes: a monitoring terminal; a threshold generator supplying a threshold voltage; a comparator to compare a monitoring voltage at the monitoring terminal and the threshold voltage; and a logic module supplying an enable signal having a brown-in logic value and a brown-out logic value. When the enable signal is at the brown-out logic value, the logic module checks transition conditions, relating to a number of usable transitions of the monitoring voltage from lower to greater than the threshold voltage, and time conditions, relating to permanence of the monitoring voltage above the threshold voltage after a usable transition or in an aggregated manner after a plurality of consecutive usable transitions. The logic module sets the enable signal to the brown-in logic value when the transition conditions or the time conditions are met.

Abstract: A control circuit for switched power supplies, for example for battery chargers, including a driving comparator of the generator of the primary current peaks generated by a power transistor that drives a load via a transformer. The aforementioned driving comparator has comparison inputs coupled to an amperometric sensor and to a circuit for determining the value of the aforementioned primary current peaks, for which the voltage applied to the load is a function of the value of the primary current peaks. The determination circuit is coupled to at least one feedback comparator and configured to regulate the value of the primary current peaks, thereby regulating the voltage applied to the load keeping the mean frequency, of the peaks close to the oscillation frequency of the clock that drives the generator.

Abstract: In some embodiments, a power supply, for example, for battery chargers of mobile telephones, includes: a control circuit having a driving terminal coupled to a control terminal of a power transistor, where the power transistor drives a primary winding of a transformer of the power supply; a current sense input for detecting a first current flowing through the power transistor; and a switched signal generator coupled to the driving terminal, the switched signal having a period that is the sum of an active time, a dead time, and a demagnetization time of the transformer. The control circuit also includes a control network coupled to the current sense input and to the switched signal generator; a regulating network having a detection unit configured to detect the first current reaching a lower limit; and a variation unit configured to increment the dead time when the active time reaches the lower limit.

Abstract: A switching converter converts an input signal to a regulated output signal using a switch and a transformer with a primary winding and a secondary winding. A wake up management circuit receives a transformer demagnetization signal and forces by wake up pulses the switch on when the switching converter operates in a burst mode. Sampled values of the transformer demagnetization signal are received. A setting circuit sets a first peak value of the current of the primary winding. A comparison circuit compare the sampled values with a voltage threshold and the preceding sampled value. In response thereto, the first peak value of the primary winding current is either maintained or a new peak value is set.

Abstract: A power switching converter includes a switch coupled to an input terminal through a primary winding of a transformer and a control circuit configured to drive the switch to provide a regulated output signal at a secondary winding of the transformer. A wake up circuit is provided to force the switching-on of the switch when the power converter enters in a burst mode. The wake up circuit includes a transmitting section coupled to the secondary winding and a receiving section coupled to an auxiliary winding of the transformer and the control circuit. The transmitting section is configured to provide a wake up signal communicated in a wireless manner to the receiving section when the output signal falls below a threshold value.

Abstract: A circuit includes a transformer with a primary, secondary, and auxiliary. A first control circuit actuates a first switch circuit based on a wake-up signal to cause the primary to transmit power to the secondary. A second control circuit actuates a second switch circuit based on an output voltage at the secondary being less than a threshold to generate the wake-up signal to the secondary for transmission to the auxiliary. The second switch circuit has a transistor with a source coupled to a reference node, a gate coupled to the second control circuit. A first diode has an anode coupled to the source and a cathode coupled to the drain, and blocks flow of current from the drain to the source. A second diode has an anode coupled to the substrate and a cathode coupled to the drain, and blocks flow of current from the drain to the substrate.

Abstract: A switching converter converts an input signal to a regulated output signal using a switch and a transformer with a primary winding and a secondary winding. A wake up management circuit receives a transformer demagnetization signal and forces by wake up pulses the switch on when the switching converter operates in a burst mode. Sampled values of the transformer demagnetization signal are received. A setting circuit sets a first peak value of the current of the primary winding. A comparison circuit compare the sampled values with a voltage threshold and the preceding sampled value. In response thereto, the first peak value of the primary winding current is either maintained or a new peak value is set.

Abstract: A switching converter converts an input signal to a regulated output signal using a switch and a transformer with a primary winding and a secondary winding. A wake up management circuit receives a transformer demagnetization signal and forces by wake up pulses the switch on when the switching converter operates in a burst mode. Sampled values of the transformer demagnetization signal are received. A setting circuit sets a first peak value of the current of the primary winding. A comparison circuit compare the sampled values with a voltage threshold and the preceding sampled value. In response thereto, the first peak value of the primary winding current is either maintained or a new peak value is set.

Abstract: A switching converter converts an input signal to a regulated output signal using a switch and a transformer with a primary winding and a secondary winding. A wake up management circuit receives a transformer demagnetization signal and forces by wake up pulses the switch on when the switching converter operates in a burst mode. Sampled values of the transformer demagnetization signal are received. A setting circuit sets a first peak value of the current of the primary winding. A comparison circuit compare the sampled values with a voltage threshold and the preceding sampled value. In response thereto, the first peak value of the primary winding current is either maintained or a new peak value is set.

Abstract: A circuit includes a transformer with a primary, secondary, and auxiliary. A first control circuit actuates a first switch circuit based on a wake-up signal to cause the primary to transmit power to the secondary. A second control circuit actuates a second switch circuit based on an output voltage at the secondary being less than a threshold to generate the wake-up signal to the secondary for transmission to the auxiliary. The second switch circuit has a transistor with a source coupled to a reference node, a gate coupled to the second control circuit. A first diode has an anode coupled to the source and a cathode coupled to the drain, and blocks flow of current from the drain to the source. A second diode has an anode coupled to the substrate and a cathode coupled to the drain, and blocks flow of current from the drain to the substrate.

Abstract: A power switching converter includes a switch coupled to an input terminal through a primary winding of a transformer and a control circuit configured to drive the switch to provide a regulated output signal at a secondary winding of the transformer. A wake up circuit is provided to force the switching-on of the switch when the power converter enters in a burst mode. The wake up circuit includes a transmitting section coupled to the secondary winding and a receiving section coupled to an auxiliary winding of the transformer and the control circuit. The transmitting section is configured to provide a wake up signal communicated in a wireless manner to the receiving section when the output signal falls below a threshold value.

Abstract: An embodiment of a voltage converter, provided with: a voltage transformer having a primary winding receiving an input voltage, a secondary winding supplying an output voltage, and an auxiliary winding supplying a feedback voltage correlated to the output voltage; a main switch, coupled to the primary winding; a control circuit, which controls switching of the main switch and has a sampling stage for sampling and holding the feedback voltage and supplying a sampled signal; and a voltage limiting circuit, provided with a clamp capacitor, designed to be coupled across the primary winding. A sampling control stage is coupled to the sampling stage, and is designed, during a given operating condition of the voltage converter, to enable updating of the sampled signal on the basis of a state of charge of the clamp capacitor.

Abstract: An embodiment of a power-supply controller comprises a switching-control circuit, an error amplifier, and a signal generator. The switching-control circuit is operable to control a switch coupled to a primary winding of a transformer, and the error amplifier has a first input node operable to receive a feedback signal, a second input node operable to receive a comparison signal, and an output node operable to provide a control signal to the switching-control circuit. The signal generator is operable to generate either the feedback signal or the comparison signal in response to a compensation signal that is isolated from a secondary winding of the transformer and that is proportional to a load current through a conductor disposed between the secondary winding and a load.

Abstract: An embodiment of a power-supply controller comprises a switching-control circuit, an error amplifier, and a signal generator. The switching-control circuit is operable to control a switch coupled to a primary winding of a transformer, and the error amplifier has a first input node operable to receive a feedback signal, a second input node operable to receive a comparison signal, and an output node operable to provide a control signal to the switching-control circuit. The signal generator is operable to generate either the feedback signal or the comparison signal in response to a compensation signal that is isolated from a secondary winding of the transformer and that is proportional to a load current through a conductor disposed between the secondary winding and a load.