A power supply includes a power converter, a protection circuit, and a control circuit. The protection circuit includes an input for receiving an input voltage, an output for providing an output voltage to the power converter, a first switching device coupled in a current path between the input and the output, and a second switching device coupled across the first switching device. The control circuit is configured to sense the input voltage and the output voltage, in response to the output voltage exceeding a first defined threshold, turn off the first switching device and turn on the second switching device to supply power to the power converter, and in response to the input voltage exceeding a second defined threshold, turn off the second switching device to disconnect the power source from the power converter. Other example power supplies and protection circuits are also disclosed.

Provided are a power supply circuit, a power supply device and a control method. The power supply circuit includes a primary rectifier unit, a modulation unit, a transformer, a secondary rectifier and filtering unit, a current feedback unit, and a control unit. The power supply circuit removes a liquid electrolytic capacitor at a primary side. Moreover, the control unit may determine a type of a voltage of input alternating current, and set a current limit value in the current feedback unit according to the type of the voltage of the alternating current.

Provided are a power supply circuit, a power supply device and a control method. The power supply circuit includes a primary rectifier unit, a modulation unit, a transformer, a secondary rectifier and filtering unit, a current feedback unit, and a control unit. The power supply circuit removes a liquid electrolytic capacitor at a primary side. Moreover, the control unit may determine a type of a voltage of input alternating current, and set a current limit value in the current feedback unit according to the type of the voltage of the alternating current.

According to one or more embodiments, a current limiting device is provided. The current limiting device includes a transformer including: a primary winding configured to accept an input current, a core electromagnetically coupled to the primary winding, and a secondary winding electromagnetically coupled to the core. The secondary winding is configured to provide a current limiting energy source based on the input current where the current limiting energy source is limited to a predetermined maximum current based on at least one characteristic of the core.

The present invention discloses parallel, series and hybrid ESD protection circuits. A preferred parallel ESD protection circuit comprises a plurality of ESD devices connected in parallel, with each comprising a resistor and an OTS component connected in series. A preferred series ESD protection circuit comprises a plurality of ESD devices connected in series, wherein the OTS components in all ESD devices are disposed on a same level. A preferred hybrid ESD protections circuit comprises ESD devices connected in parallel, as well as in series.

A driving circuit includes at least one first module, an electrostatic charge/discharge module connected to the first module and a grounding module; each first module includes a driving module, a signal transmission module and a gating module; the signal transmission module is connected to and transmits a driving signal to the driving module; the grounding module is grounded; the gating module is connected with the signal transmission module; the gating module is turned on with its turn-on voltage less than or equal to a voltage of the signal transmission module, or turned off with the turn-on voltage greater than the voltage of the signal transmission module; the turn-on voltage of the gating module is greater than that of the driving module; the charge/discharge module is connected to the gating module and the grounding module, and configured to store charges flowing therethrough and release the charges to the grounding module.

Multi-semiconductor SSPCs that solve bus level problems affecting systems as well as controller level problems affecting individual multi-semiconductor SSPCs are disclosed. Bus level and controller level problems adversely affect multi-semiconductor SSPCs and their associated systems. The disclosed multi-semiconductor SSPCs solve both bus level and controller level problems by implementing controlled rate-change of voltage (dv/dt) ramp-on rate, to ensure that the voltage on the input bus does not collapse when a multi-semiconductor SSPC is commanded closed and that a minimum amount of power is being dissipated evenly across the switching semiconductors.

An intrinsically safe (IS) multi-drop communication hub operable in a hazardous environment, including a power contact; a controller and a first signal input contact; a multiplexer communicatively connected to the controller; and a communication port communicatively connected to the controller to transmit the signal data provided by the multiplexer, wherein when the controller causes the multiplexer to supply power in a predetermined sequence to a first of the IS devices during a first time interval to generate a signal from the first of the IS devices and, after the first time interval, to a second of the IS devices during a second time interval, which does not overlap in time with the first time interval, to generate a signal from the second of the IS devices.

A method and device for temperature monitoring of a power transistor formed in a semiconductor die comprising are disclosed. A side of a temperature-sensing resistor disposed in the semiconductor die is coupled to a voltage input side of the power transistor. A controller coupled to a second side of the temperature-sensing resistor is configured to detect a voltage across the resistor and trigger a temperature related corrective action using the detected voltage.

Techniques are provided to more accurately determine reflected power, reflection coefficient, and/or voltage standing wave to permit prompt protection of components such as power amplifiers and notify communication system operators. This is accomplished by more accurately determining an amplitude and phase of an output reflected signal at an output port of a bidirectional coupler as a function of the following: an amplitude and a phase of a coupled forward signal coupled into a forward coupled port of the bidirectional coupler; an amplitude and a phase of a coupled reverse signal coupled into a reverse coupled port of the bidirectional coupler; an electrical transmission parameter from an input port of the bidirectional coupler to the forward coupled port; an electrical transmission parameter from the input port to the reverse coupled port; and an electrical transmission parameter from an output port of the bidirectional coupler to the reverse coupled port.