A power monitor includes a detecting circuit, a processing circuit, and a warning circuit. The detecting circuit detects a first abnormal condition of a primary side circuit and a second abnormal condition of a secondary side circuit. The processing circuit calculates a first class and a first occurring number of the first abnormal condition, and calculates a second class and a second occurring number of the second abnormal condition. The processing circuit determines whether the first occurring number is larger than a first predetermined number corresponding to the first class; if it is, the processing circuit outputs a first abnormal signal. The processing circuit determines whether the second occurring number is larger than a second predetermined number corresponding to the second class; if it is, the processing circuit outputs a second abnormal signal. The warning circuit outputs a warning signal according to the first or the second abnormal signal.

Multi-port power adapters. At least one example is a method including: supplying a first bus voltage to a first device by way of a DC-DC converter coupled to a link voltage; supplying a second bus voltage to a second device by way of a second DC-DC converter coupled to the link voltage; converting an AC voltage to the link voltage by way of an AC-DC converter; selecting, by a shunt regulator, a setpoint for the link voltage based on the first bus voltage and the second bus voltage; and regulating the link voltage to the setpoint by the AC-DC converter.

A power supply device includes a transformer, a first rectifier, a voltage conversion module, and a control unit. The first rectifier is connected to a primary winding of the transformer, converts a received alternating-current voltage to a first direct-current voltage. The transformer is configured to convert the first direct-current voltage to a second direct-current voltage. The voltage conversion module is connected to the secondary winding of the transformer and configured to convert the second direct-current voltage to output a third direct-current voltage. The control unit, connected to the voltage conversion module, controls the voltage conversion module to adjust an output voltage or an output current of the power supply device.

A power supply device includes a transformer, a first rectifier, a first voltage conversion module, a second voltage conversion module, and a control unit. The first rectifier, connected to a primary winding of the transformer, converts a received alternating-current voltage to a first direct-current voltage. The first voltage conversion module is connected to the first secondary winding of the transformer. The second voltage conversion module is connected to the second secondary winding of the transformer. The control unit, connected to the first voltage conversion module and second voltage conversion module, controls the first voltage conversion module or second voltage conversion module to adjust an output voltage or an output current of the power supply device.

A power supply conversion circuit and a charging device are provided. The power supply conversion circuit includes: a first voltage conversion circuit that converts a voltage when the voltage exceeds a preset voltage range and outputs the converted voltage; a post-stage voltage conversion circuit that receives the converted voltage and converts the converted voltage into a target voltage for outputting; and a signal feedback circuit that feeds back a signal to the first voltage conversion circuit according to the target voltage, so that the first voltage conversion circuit is synchronized with the post-stage voltage conversion circuit.

A power supply circuit includes a rectifier circuit, configured to convert an alternating current inputted to the rectifier circuit into a direct current; a primary power supply conversion circuit having an input end connected with an output end of the rectifier circuit, configured to convert an input voltage of the primary power supply conversion circuit which is out of a preset voltage range into an output voltage of the primary power supply conversion circuit within the preset voltage range; and a secondary power supply conversion circuit having an input end connected with an output end of the primary power supply conversion circuit, configured to convert a direct current voltage outputted by the primary power supply conversion circuit into a target direct current voltage. A lower limit of the preset voltage range is greater than a minimum working voltage of the secondary power supply conversion circuit.

Disclosed in the embodiments of the present application is a power conversion circuit, comprising a direct current conversion circuit, a pulse width control circuit, and a transformer. The transformer comprises a primary transformer coil and a secondary transformer coil. The direct current conversion circuit is connected to the primary transformer coil, and is used for adjusting an initial voltage inputted to the direct current conversion circuit to a target voltage. The pulse width control circuit is connected to the primary transformer coil, and is used for generating a pulse square wave on the basis of the target voltage. The primary transformer coil is coupled with the secondary transformer coil. The primary transformer coil is used for generating an electromagnetic filed according to the pulse square wave, and coupling the electromagnetic field to the secondary transformer coil so that the secondary transformer coil generates an output voltage.

Provided by the present disclosure are a power supply circuit and a charging device. The power supply circuit comprises a pulse transformer circuit and a first power supply conversion circuit. The pulse transformer circuit comprises a pulse transformer and a switch control circuit; a primary winding of the pulse transformer is connected to a power supply and is connected to the switch control circuit, and the switch control circuit is used to modulate the voltage on the primary winding into a pulse voltage; and the input terminal of the first power supply conversion circuit is connected to a secondary winding of the pulse transformer, and is used to transform the voltage on the secondary winding of the pulse transformer into a first preset voltage range when the voltage outputted by the secondary winding exceeds the first preset voltage range, and then output the voltage.

An isolated DC-DC converter includes a non-isolated DC-DC converter as a primary side. The non-isolated DC-DC converter includes a first inductor, a switch controller, and first and second switches. The non-isolated DC-DC converter is configured to receive an input voltage. The non-isolated DC-DC converter also includes a secondary side including a second inductor, a full wave rectifying circuit, and a filter circuit. The second inductor in the secondary side is coupled with the first inductor in the primary side to define a transformer. The secondary side is electrically isolated from the primary side by the transformer and is configured to output a DC voltage based on a voltage induced in the second inductor via the transformer.

A power converter with over temperature protection compensation includes a main conversion unit, a primary-side control unit, a secondary-side control unit, a secondary detection circuit, and an over temperature adjustment circuit. The secondary-side control unit obtains a secondary voltage change value through the secondary detection circuit, and the secondary-side control unit correspondingly provides a current change value to the over temperature adjustment circuit according to the secondary voltage change value. The over temperature adjustment circuit provides a temperature control voltage according to the current change value so that the secondary-side control unit determines whether an over temperature protection is activated according to the temperature control voltage.