The present invention relates to electrical measurement apparatus (10). The electrical measurement apparatus (10) comprises a measurement arrangement (20,24) configured to be disposed in relation to an electrical circuit (12,14,16,18) which bears an electrical signal, the measurement arrangement (20,24) being operative when so disposed to measure the electrical signal. The electrical measurement apparatus (10) further comprises a signal source (22) operative to apply a reference input signal to the measurement arrangement (20,24) whereby an output signal from the measurement arrangement comprises an electrical output signal corresponding to the electrical signal and a reference output signal corresponding to the reference input signal, the reference input signal having a substantially piecewise constant form which is repeated over each of plural cycles. The electrical measurement apparatus (10) yet further comprises processing apparatus (26) which is operative: to determine at least one cumulative representation, determination of the cumulative representation comprising summing plural received sections of the output signal, each of the plural received sections corresponding to at least a part and to a same part of the cycle of the reference input signal; and to determine at least one of: a transfer function for the measurement arrangement; a change in a transfer function for the measurement arrangement; and the electrical signal, in dependence on the at least one cumulative representation and the reference input signal.

The present invention relates to electrical measurement apparatus (10). The electrical measurement apparatus (10) comprises a measurement arrangement (20,24) configured to be disposed in relation to an electrical circuit (12,14,16,18) which bears an electrical signal, the measurement arrangement (20,24) being operative when so disposed to measure the electrical signal. The electrical measurement apparatus (10) further comprises a signal source (22) operative to apply a reference input signal to the measurement arrangement (20,24) whereby an output signal from the measurement arrangement comprises an electrical output signal corresponding to the electrical signal and a reference output signal corresponding to the reference input signal, the reference input signal having a substantially piecewise constant form which is repeated over each of plural cycles. The electrical measurement apparatus (10) yet further comprises processing apparatus (26) which is operative: to determine at least one cumulative representation, determination of the cumulative representation comprising summing plural received sections of the output signal, each of the plural received sections corresponding to at least a part and to a same part of the cycle of the reference input signal; and to determine at least one of: a transfer function for the measurement arrangement; a change in a transfer function for the measurement arrangement; and the electrical signal, in dependence on the at least one cumulative representation and the reference input signal.

Systems and methods are disclosed for monitoring a voltage received by a data storage device. A connection cable or data storage device may include a power monitoring module monitor the voltage received by the data storage device. The power monitoring module may provide an indication of whether voltage received by the data storage device is within a range of voltages.

Systems and methods are disclosed for monitoring a voltage received by a data storage device. A connection cable or data storage device may include a power monitoring module monitor the voltage received by the data storage device. The power monitoring module may provide an indication of whether voltage received by the data storage device is within a range of voltages.

To provide a current detection circuit capable of detecting with low current consumption that a prescribed current flows into a current measuring resistor. A current detection circuit is equipped with a reference voltage circuit which has two NMOS transistors having different threshold voltages and a resistor, and generates a reference voltage at the resistor, and a comparison output circuit which is comprised of a PMOS transistor, an NMOS transistor, and a measuring resistor connected in series in a manner similar to a PMOS transistor, an NMOS transistor, and a resistor and outputs a comparison result.

To provide a current detection circuit capable of detecting with low current consumption that a prescribed current flows into a current measuring resistor. A current detection circuit is equipped with a reference voltage circuit which has two NMOS transistors having different threshold voltages and a resistor, and generates a reference voltage at the resistor, and a comparison output circuit which is comprised of a PMOS transistor, an NMOS transistor, and a measuring resistor connected in series in a manner similar to a PMOS transistor, an NMOS transistor, and a resistor and outputs a comparison result.

To provide a voltage regulator which is capable of testing a phase compensation capacitor without impairing stability as a regulator and prevents a chip area from being increased. A voltage regulator is configured to be equipped with a phase compensation capacitance test circuit for a phase compensation circuit and a negative voltage detection circuit for an external output voltage adjustment terminal and to apply a negative voltage to the external output voltage adjustment terminal to thereby start up the phase compensation capacitance test circuit, and measure the discharge time or current of a phase compensation capacitor to thereby test whether the phase compensation capacitor is good or not.

To provide a voltage regulator which is capable of testing a phase compensation capacitor without impairing stability as a regulator and prevents a chip area from being increased. A voltage regulator is configured to be equipped with a phase compensation capacitance test circuit for a phase compensation circuit and a negative voltage detection circuit for an external output voltage adjustment terminal and to apply a negative voltage to the external output voltage adjustment terminal to thereby start up the phase compensation capacitance test circuit, and measure the discharge time or current of a phase compensation capacitor to thereby test whether the phase compensation capacitor is good or not.

A current detector circuit includes a current sense amplifier, coupled to a sense resistor, to receive a pair of input voltages and to output a first indicator signal responsive to a sensed input voltage difference produced by a sensed current passing through the sense resistor. The current detector circuit includes a comparator coupled to the current sense amplifier, the comparator to compare the first indicator signal to a reference voltage signal and output an interrupt signal responsive to the first indicator signal exceeding the reference voltage signal; and a reference voltage generator circuit coupled to the comparator, the reference voltage generator circuit to select the reference voltage signal from a plurality of reference voltages according to a first selector signal received from a configuration channel of a serial bus connector device.

A current detector circuit includes a current sense amplifier, coupled to a sense resistor, to receive a pair of input voltages and to output a first indicator signal responsive to a sensed input voltage difference produced by a sensed current passing through the sense resistor. The current detector circuit includes a comparator coupled to the current sense amplifier, the comparator to compare the first indicator signal to a reference voltage signal and output an interrupt signal responsive to the first indicator signal exceeding the reference voltage signal; and a reference voltage generator circuit coupled to the comparator, the reference voltage generator circuit to select the reference voltage signal from a plurality of reference voltages according to a first selector signal received from a configuration channel of a serial bus connector device.