A test verification circuit is described herein for verifying proper operation of a tested circuit, such as a voltage hazard warning circuit, using an N-channel MOSFET configured for switching ON and OFF the test verification circuit during a power outage, and a voltage source that provides an input voltage to the N-channel MOSFET from a conserved power supply. The N-channel MOSFET provides temporary power from a conserved power supply to the test verification circuit upon activation by a user during a power outage, and the test verification circuit determines whether the tested circuit has been de-energized, remains energized, or there remains inadequate power to complete the test.

A high-frequency 5 measurement method includes generating a test signal (TS), which is a sine-wave signal having a predetermined frequency, in which a period (τ) during which the power level is at a first power level and a period (T-τ) during which the power level is at a second power level lower than the first power level 10 are periodically repeated, inputting the test signal (TS) to a device under test (10) as an input signal, and measuring the difference between an output signal (OUT) of the device under test (10) and an ideal value of the output signal (OUT).

A test circuit for testing a switching device. The test circuit includes: a first terminal for receiving a drive signal; second, third and fourth terminals respectively coupled to a ground electrode, a control electrode and a power-supply electrode, of the switching device; and a clamping circuit coupled between the second terminal and the fourth terminal. The clamping circuit is configured to, upon turning on of the switching device responsive to the drive signal, cause a voltage at the third terminal to be a first voltage higher than a threshold of the switching device, and, upon turning off of the switching device responsive to the drive signal, cause the voltage at the third terminal to be a third voltage between the threshold and the first voltage, while clamping a voltage at the fourth terminal to a second voltage lower than a withstand voltage of the switching device.

A semiconductor device in which a transistor has the characteristic of low off-state current is provided. The transistor comprises an oxide semiconductor layer having a channel region whose channel width is smaller than 70 nm. A temporal change in off-state current of the transistor over time can be represented by Formula (a2). In Formula (a2), I.sub.OFF represents the off-state current, t represents time during which the transistor is off, α and τ are constants, β is a constant that satisfies 0<β≤1, and C.sub.S is a constant that represents load capacitance of a source or a drain. $\begin{array}{cc}{I}_{\mathrm{OFF}}\left(t\right)=C_S\times \frac{\alpha \times \beta }{{\tau }^{\beta }}\times t^{\beta -1}\times e^{-{\left(\frac{t}{\tau }\right)}^{\beta }}& \left(\mathrm{a2}\right)\end{array}$

Embodiments according to the invention can provide methods of testing a SiC MOSFET, that can include applying first and second voltage levels across a gate-source junction of a SiC MOSFET and measuring first and second voltage drops across a reverse body diode included in the SiC MOSFET responsive to the first and second voltage levels, respectively, to provide an indication of a degradation of a gate oxide of the SiC MOSFET and an indication of contact resistance of the SiC MOSFET, respectively.

The invention relates to a system (30) and a method for identifying a non-switching semiconductor switch (34a, 36a). The system (30) comprises a first semiconductor switch (34a), a first semiconductor component (34b), a second semiconductor switch (36a), a second semiconductor component (36b), a first resistor (64b), a second resistor (66b) and a detection unit (38). The detection unit (38) is designed to identify, on the basis of a curve of a first voltage dropping across the first resistor (64b), whether the first semiconductor switch (34a) is not switching. The detection unit (38) is designed to identify, on the basis of a curve of a second voltage dropping across the second resistor (66b), whether the second semiconductor switch (36a) is not switching.

A semiconductor device includes: a semiconductor body; an electrical device formed in an active region of the semiconductor body, the active region including an interface between the semiconductor body and an insulating material; and a sensor having a bandwidth tuned to at least part of an energy spectrum of light emitted by carrier recombination at the interface when the electrical device is driven between accumulation and inversion, wherein an intensity of the emitted light is proportional to a density of charge trapping states at the interface, wherein the sensor is configured to output a signal that is proportional to the intensity of the sensed light. Corresponding methods of monitoring and characterizing the semiconductor device and a test apparatus are also described.

A fault detection circuit includes a short circuit comparison circuit which has a first input connected to the source of the second NFET, a second input, and an output. The circuit includes an over-current comparison circuit which has a first input connected to the source of the second NFET, a second input, and an output. The circuit includes a voltage divider circuit which has a first terminal connected to first input of the short circuit comparison circuit, a second terminal connected to the first input of the over-current comparison circuit, and a third terminal connected to a ground terminal. The circuit includes a delay circuit which has an input connected to the output of the over-current comparison circuit and has an output.

The systems and methods described herein are for remaining useful life prediction in electronics and include measuring a plurality of circuit parameters for each of a plurality of circuit components at a plurality of different temperatures, determining a probability density function of failure as a function of time for each of the plurality of circuit components and combining the probability density functions for each of the plurality of circuit components as a function of a circuit that contains the plurality of circuit components.

A state detection circuit for detecting whether a state of an input node is floating, grounded, or electrically connected to an external voltage includes: a unidirectional device circuit and a determination circuit. The unidirectional device circuit electrically conducts a test node to a detection node unidirectionally. The detection node is coupled to the input node. The test node, the unidirectional device circuit, the detection node and the input node form a current path. The determination circuit determines a state of the input node according to a voltage level of the detection node. Within a detection stage, the state detection circuit provides a test voltage at the test node. A voltage of the detection node is determined by the input node, the test voltage, and a characteristic of the unidirectional device circuit.