The present invention provides a voltage monitoring apparatus capable of stable operation even in a low-voltage region. The voltage monitoring apparatus (1) includes: an inner voltage generating portion (40), lowering an input voltage (VIN) to generate an inner voltage (Vreg); an input voltage monitoring portion (30), receiving a power supply from an output terminal of the inner voltage generating portion (40) to operate; a switch portion (50), disposed between an input terminal of the input voltage (VIN) and the output terminal of the inner voltage generating portion (40); and a switch driving portion (60), turning on the switch portion (50) when the input voltage (VIN) is lower than a threshold voltage (for example, Vy<Vref), and turning off the switch portion (50) when the input voltage (VIN) is higher than the threshold voltage (for example, Vy>Vref). Furthermore, the threshold voltage is preferably set as, for example, turning off the switch portion (50) upon the inner voltage generating portion (40) changing to a state capable of outputting the inner voltage (Vreg) that is at least higher than a minimum operating voltage of the input voltage monitoring portion (30).

Systems and methods for power distribution are disclosed. A system includes a first power domain that supplies current to an integrated circuit at a first voltage level, a second power domain that supplies current to the integrated circuit at a second voltage level, and a current distribution component that is connected to the first power domain and connectable to the second power domain and senses a metric comprising a first current level or a first voltage level drawn from the first power domain, determines whether the metric exceeds a first threshold, and in response to determining that the metric exceeds the first threshold, electrically connects the second power domain to the integrated circuit to supply additional current such that an aggregate current level received by the integrated circuit comprises current from the first power domain and the additional current from the second power domain.

A circuit includes an input terminal, a first transistor, a second transistor, a comparator, a voltage reference circuit, and a control circuit. The first transistor includes a first terminal coupled to the input terminal. The second transistor includes a first terminal coupled to the input terminal. The comparator includes a first terminal coupled to the input terminal. The voltage reference circuit is coupled to a second terminal of the comparator. The control circuit includes an input, a first output, and a second output. The input is coupled to an output of the comparator. The first output is coupled to a second terminal of the first transistor. The second output is coupled to a second terminal of the second transistor.

A current detection circuit, a semiconductor device and a semiconductor system which are capable of improving current detection accuracy are provided. According to one embodiment of the invention, a current detection circuit includes a resistive element to convert an input current supplied from outside into an input voltage, a constant-current source, a resistive element to convert an output current of the constant-current source into a reference voltage, and an AD converter to AD-convert the input voltage using the reference voltage.

In described examples, a method of determining whether there is an open load fault in a test circuit includes closing a first switch to couple an input voltage to a first LC filter in which a first capacitor is coupled to a ground, the first LC filter coupled to a first terminal coupled to the test circuit; and closing a second switch to couple the input voltage to a second LC filter in which a second capacitor is coupled to the ground, the second LC filter coupled to a second terminal coupled to the test circuit. After the LC filters charge to the input voltage, the second switch is opened, and the second capacitor is discharged across a discharge resistor for a specified discharge time. The voltage across the discharge resistor falling below a reference voltage indicates that there is an open load fault in the test circuit.

A load switch circuit includes a charging transistor, a current sensor, a voltage sensor, a selector, a current controller and a mode controller. The charging transistor is connected between a first switch node and a second switch node and controls a charging current in response to a charging control signal. The current sensor is connected to the first switch node and the second switch node and senses the charging current to generate a current sensing signal. The voltage sensor is connected to the first switch node and the second switch node and senses a source-drain voltage of the charging transistor to generate a voltage sensing signal. The selector selects the current sensing signal or the voltage sensing signal in response to a mode signal to generate a selection voltage signal. The current controller compares the selection voltage signal with a reference voltage to generate the charging control signal.

A semiconductor device is provided and includes: a voltage sensing circuit configured to output first and second sensing voltages based on a target voltage applied thereto; and a comparing circuit configured to generate a monitoring output signal based on levels of the first and second sensing voltages, wherein the voltage sensing circuit includes: a first transistor including a gate to receive a reference bias voltage, a source connected to an input node, and a drain connected to one end of a first resistive element; a second transistor provided in a current mirror structure with the first transistor, and including a drain connected to a third resistive element; and a second resistive element connected to another end of the first resistive element, the first sensing voltage being provided to both ends of the second resistive element, and the second sensing voltage being provided to both ends of the third resistive element.

Systems, methods, techniques and apparatuses of short circuit protection are disclosed. One exemplary embodiment is a method for protecting a semiconductor switch comprising receiving a measurement corresponding to an electrical characteristic of the semiconductor switch; determining a semiconductor switch resistance value using the received measurement; estimating a junction temperature of the semiconductor switch using the semiconductor switch resistance value; determining a short circuit voltage threshold using the estimated junction temperature; comparing the short circuit voltage threshold to a test voltage corresponding to a drain-source voltage of the semiconductor switch; determining a short circuit condition is occurring in response to comparing the short circuit voltage threshold and the test voltage; and opening the semiconductor switch in response to determining the short circuit condition is occurring.

An electronic circuit comprises a power switch circuit and a fault detection circuit. The power switch circuit includes a transistor. The fault detection circuit includes a first comparator circuit configured to compare a monitored voltage of the transistor to a detection threshold voltage and produce an indication of a circuit fault according to the comparing, and a delay circuit configured to delay the comparing by the first comparator circuit according to slew rate of the monitored voltage.

A method includes selecting a state model control, as an operational state of the heater, from among a plurality of state model controls, measuring an electrical characteristic of the heater, where the electrical characteristic includes at least one of an electric current and a voltage, and controlling power to the heater based on the selected operational state and based on the measured electrical characteristic.