An integrated circuit for a power supply circuit that includes a transformer and a transistor controlling an inductor current flowing through a primary winding of the transformer. The integrated circuit includes a terminal receiving a voltage corresponding to the voltage of a secondary winding of the transformer when the transistor is in an off-state, a first detection circuit detecting that the inductor current is smaller than a first current value, and a determination circuit determining whether an AC voltage applied to the primary winding of the transformer is a first or second AC voltage, both based on the received voltage in the off-state of the transistor. The integrated circuit is configured to drive the transistor in response to a detection result of the first detection circuit, a determination result of the determination circuit, and an output voltage of the power supply circuit generated from the AC voltage.

A voltage adjustment apparatus, a chip, a power source, and an electronic device. The apparatus comprises: a voltage input module, used for receiving an input voltage; a current determining module, electrically connected to the voltage input module and used for determining an adjustment current on the basis of the input voltage and a load current; a control module, electrically connected to the current determining module and used for outputting a control signal on the basis of the adjustment current; and a voltage output module, electrically connected to the voltage input module, the current determining module, and the control module, and being used for outputting a target voltage on the basis of the control signal and the input voltage.

A switching control circuit for controlling an LLC converter that includes a first switching device, a first free-wheeling diode connected in parallel with the first switching device, a second switching device connected in series with the first switching device and the first free-wheeling diode, and a second free-wheeling diode connected in parallel with the second switching device. The switching control circuit controls switching of the first and second switching devices. The switching control circuit includes a determination circuit determining whether an operation mode of the LLC converter is a first mode or a second mode based on the resonant current of the LLC converter, and a drive signal output circuit outputting first and second drive signals for respectively switching the first and second switching devices based on the determined operation mode, to thereby prevent a shoot-through current from flowing through the first switching device or the second switching device.

An integrated circuit for a power supply circuit configured to generate an output voltage at a target level. The power supply circuit includes a transistor configured to control an inductor current flowing through an inductor. The integrated circuit includes a load detection circuit outputting a detection voltage corresponding to a power consumption of a load and corresponding to an operation mode of the power supply circuit, based on the inductor current, a driver circuit driving the transistor according to the operation mode of the power supply circuit, and a control circuit configured to control the driver circuit to switch the power supply circuit to a second mode upon the detection voltage reaching a first level with a decrease in the power consumption of the load, and to a first mode upon the detection voltage reaching a second level with an increase in the power consumption of the load.

The present disclosure provides a power factor improvement circuit with a DC/DC converter including an arithmetic circuit. A first voltage having a full-wave rectified waveform is received by an input voltage detection terminal of the power factor improvement circuit. A second voltage is generated by amplifying an error between a first detection voltage and a reference voltage according to an output voltage of the DC/DC converter. A third voltage is generated by multiplying the first voltage by the second voltage. The arithmetic circuit adds an offset voltage to a third voltage to generate a fourth voltage. A comparator is configured to compare a second detection voltage with the fourth voltage. A drive circuit is configured to turn on/off drive of the switching transistor according to an output of the comparator. When the second detection voltage is higher than the fourth voltage, the switching transistor is turned off.

An apparatus includes a buck converter portion of a buck-boost converter configured to operate under a constant on-time control scheme, wherein an on-time of a high-side switch of the buck converter portion is determined by a buck on-time timer, and a boost converter portion of the buck-boost converter configured to operate under a constant off-time control scheme, wherein an off-time of a low-side switch of the boost converter portion is determined by a boost off-time timer.

A voltage converter includes a capacitive voltage conversion circuit, an output capacitor, an inductor, a current detector, and a controller. The capacitive voltage conversion circuit includes switches, at least one flying capacitor, and an intermediate capacitor at an output portion. The current detector detects a current flowing in the inductor. The controller controls the switches in the capacitive voltage conversion circuit to change between at least two states by comparing the current flowing in the inductor to a threshold current.

An architecture for a multi-port AC/DC Switching Mode Power Supply (SMPS) with Power Factor Correction (PFC) comprises power management control (PMC) for PFC On/Off Control and Smart Power Distribution, and optionally, a boost follower circuit. For example, in a universal AC/DC multi-port USB-C Power Delivery (PD) adapter, PMC enables turn-on and turn-off of PFC dependent on output port operational status and a combined load of active output ports. A microprocessor control unit (MCU) receives operational status, a voltage sense input and a current sense input for each USB port, computes output power for each USB port, and executes a power distribution protocol to turn-on or turn-off PFC dependent on the combined load from each USB port. Available power may be distributed intelligently to one or more ports, dependent on load. In an example embodiment, turning-off PFC for low load and low AC line input increases efficiency by 3% to 5%.

A control circuit for a power factor correction (PFC) circuit, the control circuit includes a multiplier having first, second, and third multiplier inputs and a multiplier output. The control circuit has an adder having first and second inputs and an output. The first input of the adder is coupled to the multiplier output. The control circuit further includes a root mean square (RMS) calculation circuit configured to determine a square of a root mean square of an input sinusoidal voltage. The RMS calculation circuit has an output coupled to the second multiplier input. An input voltage square calculation circuit is configured to determine a square of the input sinusoidal voltage. The input voltage square calculation circuit has an output coupled to the third multiplier input.

In a power conversion system, a power converter includes a power conversion circuit connected to a direct current (DC) source via a DC distribution line and converts and supplies received DC power to a load, and a power conversion control unit. A power stabilizing device is disposed between the DC distribution line and the power converter and stabilizes a DC voltage applied from the DC power source. A control power source of the power stabilizing device performs current control of the current transformer to suppress DC magnetization caused by a DC current component of the primary current while compensating for a varying component of the DC voltage. The control power source acquires current information or voltage information calculated from control information used by the power conversion control unit for control operations related to energization of the load and uses it as control information for the power stabilizing device.