The present invention aims to reduce the leakage current that flows when measuring a high voltage and includes: a voltage detector that detects a voltage and outputs a detection voltage; a current supplier that supplies a measurement current across a pair of input terminals via a protective resistor; and a processor that executes a voltage measurement process, which measures the voltage based on data indicating the detection voltage, and a resistance measurement process, which measures a resistance connected between the input terminals based on the voltage and the current. A first switch is connected in parallel to the protective resistor and the processor executes the voltage measurement process in a state where the first switch has been set open to measure the terminal voltage, and executes the resistance measurement process by setting the first switch shorted when the voltage is equal to or below the reference voltage value.

The present invention aims to reduce the leakage current that flows when measuring a high voltage and includes: a voltage detector that detects a voltage and outputs a detection voltage; a current supplier that supplies a measurement current across a pair of input terminals via a protective resistor; and a processor that executes a voltage measurement process, which measures the voltage based on data indicating the detection voltage, and a resistance measurement process, which measures a resistance connected between the input terminals based on the voltage and the current. A first switch is connected in parallel to the protective resistor and the processor executes the voltage measurement process in a state where the first switch has been set open to measure the terminal voltage, and executes the resistance measurement process by setting the first switch shorted when the voltage is equal to or below the reference voltage value.

A current sensor comprises: a plurality of magnetoresistance elements whose resistance value changes by application of an current-induced magnetic field from a current-to-be-measured; and a selection circuit that selects one magnetoresistance element from these plurality of magnetoresistance elements and outputs a signal of a selected magnetoresistance element. In the plurality of magnetoresistance elements, relationships between a magnitude of the applied current-induced magnetic field and the resistance value are different from each other.

A current sensor comprises: a plurality of magnetoresistance elements whose resistance value changes by application of an current-induced magnetic field from a current-to-be-measured; and a selection circuit that selects one magnetoresistance element from these plurality of magnetoresistance elements and outputs a signal of a selected magnetoresistance element. In the plurality of magnetoresistance elements, relationships between a magnitude of the applied current-induced magnetic field and the resistance value are different from each other.

A current sensor includes a first resistor between a first node and a second node, a first voltage limiting device between the first node and the second node, and a second resistor between the second node and a third node, wherein a resistance level of the first resistor is greater than a resistance level of the second resistor, and wherein a current flowing from the third node to the first node is configured to be measured based on a voltage across the first resistor or a voltage across the second resistor.

A current sensor includes a first resistor between a first node and a second node, a first voltage limiting device between the first node and the second node, and a second resistor between the second node and a third node, wherein a resistance level of the first resistor is greater than a resistance level of the second resistor, and wherein a current flowing from the third node to the first node is configured to be measured based on a voltage across the first resistor or a voltage across the second resistor.

Methods and circuits for detecting an ion current in a mass spectrometer are described. A circuit and a method may involve converting, over a length of integration time, the ion current to a voltage ramp by an integrating circuit having a gain setting. The circuit and the method may also involve determining a slope of the voltage ramp. The circuit and the method may also involve determining a magnitude of the ion current based on the slope of the voltage ramp and the gain setting. The circuit and the method may further involves determining an out-of-range state based on the voltage ramp and adjusting the gain setting of the integrating circuit, or the length of integration time or both, in response to the determining of the out-of-range state.

A control method of a semiconductor device includes inspecting an electrical property of a current detection circuit in the first semiconductor chip, writing information on a correction equation obtained on the basis of an inspection result in a memory circuit of the second semiconductor chip, and correcting, with the second semiconductor chip, a detection result obtained by the current detection circuit on the basis of the information on the correction equation.

An apparatus for detecting a change in a voltage level of a power supply is disclosed. An inverter coupled to a first power supply may generate a signal dependent upon a voltage level of a second power supply. A latch coupled to the first power supply may be set based on a first voltage level of the second power supply and a first value of the signal, and re-set based on a second voltage level of the second power supply and a second value of the signal different than the first value of the signal.

An apparatus for detecting a change in a voltage level of a power supply is disclosed. An inverter coupled to a first power supply may generate a signal dependent upon a voltage level of a second power supply. A latch coupled to the first power supply may be set based on a first voltage level of the second power supply and a first value of the signal, and re-set based on a second voltage level of the second power supply and a second value of the signal different than the first value of the signal.