A flyback power converter circuit includes a transformer, a blocking switch, a primary side switch, a primary side controller circuit and a secondary side controller circuit. The transformer is coupled between an input voltage and an internal output voltage in an isolated manner. The blocking switch controls the electric connection between the internal output voltage and an external output voltage. In a standby mode, the internal output voltage is regulated to a standby voltage, and the blocking switch is controlled to be OFF; in an operation mode, the internal output voltage is regulated to an operating voltage, and the blocking switch is controlled to be ON, such that the external output voltage has the operating voltage. The standby voltage is smaller than the operating voltage, so that the power consumption of the flyback power converter circuit is reduced in the standby mode.

The present disclosure provides a control system of a buck converter, relating to the field of Internet of Things. The control system of a buck converter provided in an embodiment of the present disclosure includes a first control module, a second control module, and a mode selector. The first control module is turned on and the second control module is turned off through an analog current sensor in the mode selector when an IoT device switches from a transmission mode to a sleep mode or a standby mode, so that the first control module outputs a first voltage pulse to the driving and level shifter module, wherein a frequency of the first voltage pulse is determined by a frequency of a first clock in the first control module, and a width of the first voltage pulse is determined by a frequency of a second clock in the first control module.

A first comparator is enabled during a period in which a wake-up signal is asserted and asserts a first detection signal indicative of a comparison result between a first feedback voltage generated by a first voltage dividing circuit and a first threshold voltage. A second comparator is always enabled and asserts a second detection signal indicative of a comparison result between a second feedback voltage V.sub.FB generated by a second voltage dividing circuit and a second threshold voltage V.sub.TH. A logic circuit generates a first pulse signal based on a first detection signal or a second detection signal, asserts the wake-up signal in a non-light load state, and negates the wake-up signal in a light load state.

A control circuit for a power converter apparatus includes a reference voltage source that generates a predetermined reference voltage; an output voltage detection circuit having a capacitor that charges the output voltage or a corresponding voltage, the output voltage detection circuit detecting a drop in the output voltage based on a voltage across the capacitor; a feedback voltage output circuit including two voltage-divider resistors connected in series with each other with a voltage divider ratio set according to the reference voltage and the output voltage, the feedback voltage output circuit outputting a feedback voltage obtained by dividing the output voltage; a voltage comparison circuit that compares the reference voltage with the feedback voltage, and outputs a comparison result signal; and a drive control circuit configured to control intermittent operation in accordance with the comparison result signal and a detection signal of the output voltage detection circuit.

A power supply for an LED lighting unit. The power supply comprises two power converters, either of which may provide the power to be drawn by components of the LED lighting unit. In particular, a controller of the power supply controls which power converter converts a mains power supply to a power level for a connected LED lighting unit. The two power converters are designed to be efficient when providing different power levels.

A multi-level power converter and a method using first, second, third and fourth switching elements, an inductor, and a flying capacitor are presented. A first terminal of the inductor may be connected to a switching terminal connecting the second and third switching elements. A first terminal of the flying capacitor may be connected to a terminal connecting the first and second elements. A second terminal of the flying capacitor may be connected to a terminal connecting the third and fourth switching elements. The multi-level power converter may have a first feedback circuit to generate control signals for setting the switching elements in a plurality of switching states for regulating an output voltage or an output current. The converter may have a second feedback circuit to generate control signals to allow the flying capacitor to be charged or discharged using an inductor current flowing through the inductor.

A method for controlling a battery-powered power supply. The method includes generating a first output from a first power supply within the battery-powered power supply. The first output is coupled to an output bus. The method further includes monitoring a voltage of the output bus, and determining, using a controller of the battery-powered power supply, whether the voltage of the output bus is less than a first predetermined level. The method further includes deactivating the first power supply in response to determining that the voltage of the output bus is below the first predetermined level, and generating a second output from a second power supply within the battery-powered power supply. The second output is configured to be coupled to the output bus. The second power supply has a higher output rating than the first power supply.

A charging control method includes: converting an input power to a DC power; receiving the DC power by a detachable cable to generate a bus power; converting the bus power to a charging power for charging a battery in a charging period; and adjusting the DC power and/or the charging power to track a maximum of a power conversion efficiency; wherein the power conversion efficiency includes one of the following: an input power conversion efficiency, which is a conversion efficiency of converting the input power to the charging power; a DC power conversion efficiency, which is a conversion efficiency of converting the DC power to the charging power; or a bus power conversion efficiency, which is a conversion efficiency of converting the bus power to the charging power.

In some examples, a device for controlling a transistor in a power converter system includes a first circuit configured to generate an error current based on a difference between a reference signal and a feedback signal, where the feedback signal depends on an output voltage of the power converter system. The device also includes a frequency generator configured to generate an activation signal based on the difference between the reference signal and the feedback signal. The device further includes a pedestal circuit configured to define a peak current threshold for the transistor based on an offset value. The device also includes a logic circuit configured to activate the transistor based on the activation signal and deactivate the transistor when a current sense signal reaches the defined peak current threshold, where the current sense signal is representative of a power current conducted by the transistor.

Methods and apparatuses for regulating a power converter are described. A device comprising a control circuit and a logic circuit can be integrated in a controller coupled to the power converter. The control circuit can generate a constant off-time signal based on a ramp signal and an error signal. The logic circuit can generate a control signal based on the constant off-time signal and a constant on-time signal. The logic circuit can output the control signal to the power converter. In response to an on-time period of the constant off-time signal being less than an on-time period of the constant on-time signal, the control signal can vary according to the constant on-time signal. In response to the on-time period of the constant off-time signal being greater than the on-time period of the constant on-time signal, the control signal can vary according to the constant off-time signal.