In one embodiment, a power supply circuit has a power source, an inductor in series with a switching transistor connected to the power source, a pair of isolation capacitors connected across the switching transistor, a load connected to the isolation capacitors such that they isolate the load from low frequency energy from the power source, and a resonance circuit configured to amplify resonant ringing connected at least one of in parallel to the inductor or in parallel to the switching transistor.

An integrated circuit for a power supply including a power transistor, the integrated circuit being configured to switch and drive the power transistor. The integrated circuit includes: a first terminal to which a first switch is coupled; a first determination circuit configured to determine, based on a voltage level at the first terminal, whether to operate the integrated circuit in a first mode or a second mode, a power consumption in the second mode being greater than a power consumption in the first mode; a first power supply voltage generation circuit configured to stop generating a first power supply voltage when the integrated circuit operates in the first mode, and generate the first power supply voltage when the integrated circuit operates in the second mode; and a driver circuit configured to receive the first power supply voltage, to switch and drive the power transistor.

System and method for transmitting and receiving. For example, the system includes a transmitter, one or more wires, and a receiver connected to the transmitter through the one or more wires. The transmitter is configured to generate a first current, and the receiver is configured to receive the first current. The receiver includes a coil, a Hall effect sensor, and a comparator, and the Hall effect sensor includes a first electrode and a second electrode. The coil is electrically isolated from the Hall effect sensor and configured to generate a magnetic field based at least in part on the first current flowing through the coil, and the Hall effect sensor is configured to sense the magnetic field and generate a first voltage at the first electrode and a second voltage at the second electrode. The comparator includes a first input terminal and a second input terminal.

A driver circuit is configured to control a power transistor. The driver circuit comprises a signal generator configured to generate a control signal for the power transistor based on a supply signal and an input signal from a control unit. In addition, the driver circuit includes a ripple detector configured to receive the supply signal and determine whether the supply signal includes a ripple error. In some examples, the ripple detector may be configured to send a warning signal to the control unit in response to detecting the ripple error.

Controllers for power converters, power converters and corresponding methods are provided.

A controller of a power converter including a first power stage and a second power stage receives an indication of an output voltage of the power converter, where the indication is measured at the primary side of the power converter. Based on the indication, a control related to an intermediate voltage of the power converter is performed.

An integrated circuit for a power supply circuit including a transformer having a primary coil, a secondary coil, and an auxiliary coil, and a transistor configured to control a current flowing through the primary coil. The integrated circuit includes a first terminal receiving a power supply voltage corresponding to a voltage from the auxiliary coil; a second terminal receiving a feedback voltage corresponding to an output voltage; a third terminal receiving a voltage corresponding to a current flowing through the transistor when the transistor is on; a determination circuit determining whether a detection circuit configured to detect a voltage generated in the auxiliary coil is coupled between the third terminal and the auxiliary coil; and a switching control circuit controlling switching of the transistor based on the voltages at the second and third terminals and a determination result of the first determination circuit.

An isolated power supplies converts an input power source in a primary side into an output power source in a secondary side, capable of transmitting a signal from the secondary side to the primary side via a transformer. The transformer has a primary winding connected with a main switch, and a secondary winding connected with a secondary-side switch. A primary-side controller controls the main switch. A secondary-side controller controls the secondary-side switch and detects a demagnetization time of the transformer. Before the end of the demagnetization time, the secondary-side controller turns OFF the secondary-side switch to signal, via the transformer, the primary-side controller, which in response turns ON the main switch to operate the isolated power supply in a continuous-conduction mode or in a boundary mode.

A switching power converter is provided with an overvoltage protection circuit that monitors the differential data signal voltages in a data interface such as a USB data interface powering a load device to detect soft short conditions.

Methods, apparatuses, computer program products, and computer readable media are disclosed herein. In one aspect, an apparatus includes a first capacitor, a first inductor in resonance with the first capacitor, a first electronic switch and a second electronic switch. The first electronic switch may be configured to cause, when the first electronic switch is closed, the first capacitor to store a first energy, and to cause a second energy to be stored in magnetic fields of the inductor. The second energy may be transferred to a load during a resonant portion of an energy transfer cycle. The apparatus may further include a second electronic switch configured to cause the stored first energy in the first capacitor to be transferred at least in part to the magnetic fields of the inductor, and then transferred to the load during a buck portion of the energy transfer cycle.

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 an input signal at the first controller terminal and generate a drive signal at the second controller terminal based at least in part on the input signal to turn on or off a transistor in order to affect a current associated with a secondary winding of the power converter. Additionally, the system controller is further configured to determine whether the input signal remains larger than a first threshold for a first time period that is equal to or longer than a first predetermined duration.