The voltage monitoring circuit according to one embodiment of the present invention comprises: a clamping unit for clamping the voltage of input power supplied from a power source to base voltage, and outputting to an MCU; and a switch unit for cutting off the input power from the power source if an anomaly occurs with the base voltage of the clamping unit.

A power device fault detection circuit includes a first fault detector configured to measure an output signal of at least one power device and output a first fault signal when a voltage of the output signal of the at least one power device exceeds a first voltage reference level after a first time period; and a second fault detector configured to measure an output signal of the at least one power device and output a second fault signal when a voltage of the output signal of the at least one power device exceeds a second voltage reference level after a second time period, where the first time period implemented by the first fault detector is shorter than the second time period implemented by the second fault detector.

An interface protection circuit and a device interface are disclosed. The interface protection circuit includes a capacitor and a transient voltage suppressor (TVS) transistor. A first end of the capacitor is connected to a connection port, a second end of the capacitor is connected to a first end of the TVS transistor and an interface chip, and a second end of the TVS transistor is grounded.

An electronic system for a surgical instrument is disclosed. The electronic system comprises a main power supply circuit configured to supply electrical power to a primary circuit. A supplementary power supply circuit configured to supply electrical power to a secondary circuit. A short circuit protection circuit coupled between the main power supply circuit and the supplementary power supply circuit. The supplementary power supply circuit is configured to isolate itself from the main power supply circuit when the supplementary power supply circuit detects a short circuit condition at the secondary circuit. The supplementary power supply circuit is configured to rejoin the main power supply circuit and supply power to the secondary circuit, when the short circuit condition is remedied.

A charging port protection apparatus and a terminal related to the field of terminal technologies are provided, including a first detection circuit, a first discharge circuit, a second detection voltage, and a switch circuit. The first detection circuit generates a first detection voltage based on a peak voltage of an input voltage. The first discharge circuit discharges the peak voltage based on the first detection voltage. The second detection circuit generates a second detection voltage when the input voltage is greater than a first threshold. The switch circuit disconnects the input voltage based on the second detection voltage. This implements not only protection against an ESD and EOS peak voltage, but also protection against a high-voltage direct current. The protection against the peak voltage and the protection against the high-voltage direct current are not mutually limited, which implements protection against impact of electrical over-stress in various forms.

A protection circuit for connecting and disconnecting to a DC power source, and a DC operated device including such a protection circuit. The protection circuit has input terminals for receiving power from a DC power source and output terminals for providing power to a DC operated device; a first stage with a voltage measurement circuit coupled between the input terminals; and a second stage following the first stage including a pre-charge control circuit. The protection circuit further includes a digital controller arranged for controlling activating and de-activating a local PSU for supplying power to electronics of the DC operated device. The digital controller is arranged for measuring a voltage of the voltage measurement circuit and de-activating the local PSU when detecting a voltage drop on the first input terminal that exceeds a predetermined threshold dip and/or threshold slope.

An aspect of the present invention is a voltage supply device including: a controller which outputs a signal indicating any one bus voltage determined by negotiation among a plurality of bus voltages from a power supply circuit to an external device; a reference voltage generation unit which generates a reference voltage corresponding to the signal; a detection voltage output unit which detects the bus voltage and outputs a detection voltage; a comparison unit which compares the detection voltage with the reference voltage; and a switch unit which switches the supply state of the bus voltage to the external device in response to the comparison result.

An embodiment of the present disclosure relates to an electronic circuit including a first switch coupling a first node of the circuit to an input/output terminal of the circuit; a second switch coupling the first node to a second node of application of a fixed potential; and a highpass filter having an input coupled to the terminal and an output coupled to a control terminal of the second switch.

In described examples, a circuit includes a reference voltage, a driving circuit with a driving input and a driving output, an output transistor, and a clamp circuit with a clamp input and a clamp output. The output transistor includes a source, a drain, and a gate; the source is coupled to receive the reference voltage. The clamp input is coupled to the driving output and to the gate. The clamp output is coupled to either the driving input or to the driving output, the gate, and the clamp input. The clamp circuit is configured to detect an operating region of the output transistor and to generate a clamping current after the output transistor enters a triode region. The clamping current is selected to prevent an absolute value of a source-gate voltage of the output transistor from equaling or exceeding a gate oxide tunneling voltage of the output transistor.

Systems and methods of determining fault location on a DC microgrid feeder need to be extremely fast to protect the circuit breaker and converter-source components. This disclosure develops a seminal theoretical foundation for fast fault location on a DC feeder that uses only single-ended local measurements in time domain. The theory provides a closed-form deterministic solution for fault location, making the resulting fault location method agnostic to system-topology and immune to fault resistance. The theory is developed with ideal DC voltage sources and is extended to practical converter-sources. The performance of the resulting method is demonstrated by simulating a DC feeder with converters connected at both ends, modeled in PSCAD (power systems computer-aided design).