A monitored system capable of computing the number of complex operations of various typologies is composed of a plurality of simple operations performed by machines of various types. The system uses the reading of the variations in the electrical absorption of the machines associated with the absorption time and the typology of machine.

One example discloses a current monitoring device, including: a sense impedance configured to receive a current to be monitored; an impedance divider, coupled to the sense impedance, and configured to convert the current to be monitored to a differential voltage to be monitored; a reference circuit configured to generate a differential reference voltage; a comparator coupled to the impedance divider and the reference circuit and configured to output a signal if the differential voltage to be monitored is different than the differential reference voltage; and wherein the reference circuit includes a comparator trimming circuit configured to vary the differential reference voltage to compensate for offset biases in the comparator.

Methods and systems are described for monitoring and compensating an offset between a reference voltage used in a first device and a corresponding reference voltage used in a second device. The first device can include offset circuitry. The offset circuitry receives two voltage signals. The first voltage signal is equal to a first voltage value that is used as a reference voltage in the first device. The second voltage signal can be a time-varying voltage signal that has a known relationship with a second voltage value that is used as a reference voltage in the second device. The offset circuitry can then determine the second voltage value from the second voltage signal, and output an offset value based on a difference between the first voltage value and the second voltage value.

Methods and systems are described for monitoring and compensating an offset between a reference voltage used in a first device and a corresponding reference voltage used in a second device. The first device can include offset circuitry. The offset circuitry receives two voltage signals. The first voltage signal is equal to a first voltage value that is used as a reference voltage in the first device. The second voltage signal can be a time-varying voltage signal that has a known relationship with a second voltage value that is used as a reference voltage in the second device. The offset circuitry can then determine the second voltage value from the second voltage signal, and output an offset value based on a difference between the first voltage value and the second voltage value.

A system for an aircraft includes an aircraft component that includes a heater routed through the aircraft component, the heater including a resistive heating element and insulation surrounding the resistive heating element. A first current flows into the resistive heating element to provide heating for the aircraft component and a second current flows out of the resistive heating element. The system further includes a first sensor configured to produce a first sensor signal representing the first current, a second sensor configured to produce a second sensor signal representing the second current, a leakage sensor configured to produce a leakage sensor signal representing a leakage current, and a signal processor configured to sample and measure the first current, the second current, and a leakage current using a high frequency sampling rate to identify the presence of electric arcing. The detection of electric arcing is used to predict future heater failure and estimate heater remaining useful life.

A method and apparatus for sensing a common mode feedback current are provided. The common mode feedback current may flow through a common mode resistive divider of a piezoresistive bridge. A first current mirror mirrors the common mode feedback current and provides a first mirrored common mode current. A current aggregation stage receives the first mirrored common mode current and determines a bridge current of the piezoresistive bridge based on the first mirrored common mode feedback current. A second current mirror may be used to mirror the first current mirror before determining the bridge current.

Differential sampling circuits may be adversely affected by changes in common mode voltage. Changes in the common mode voltage may alter the on resistance of transistor switches which it turn may mean that small signal changes are not correctly observed against a bigger common mode signal. The present disclosure relates to a way of improving the ability to resolve small differential signal changes by varying the supply or drive voltage to a component to compensate for common mode voltage changes.

Differential sampling circuits may be adversely affected by changes in common mode voltage. Changes in the common mode voltage may alter the on resistance of transistor switches which it turn may mean that small signal changes are not correctly observed against a bigger common mode signal. The present disclosure relates to a way of improving the ability to resolve small differential signal changes by varying the supply or drive voltage to a component to compensate for common mode voltage changes.

Power converter circuits, including DC-DC converter circuits, that conserve IC area by utilizing more area-efficient alternatives for measurement circuitry. Various embodiments include a power converter circuit including a charge pump having a plurality of stack-nodes V.sub.CXM and at least one multiplexor for coupling selected stack-nodes V.sub.CXM to a corresponding comparator circuit configured to output a signal indicative of a difference between a selected input to the multiplexor and a reference signal. The number of comparator circuits is less than (N1)M, where N is the conversion gain of the power converter circuit (i.e., the number of charge pump stages X plus one), and M is the number of parallel charge pump legs. Related methods include measuring voltages at stack-nodes V.sub.CXM in a charge pump, wherein the stack-nodes V.sub.CXM are selected by means of a multiplexor and an input to a comparator.

Power converter circuits, including DC-DC converter circuits, that conserve IC area by utilizing more area-efficient alternatives for measurement circuitry. Various embodiments include a power converter circuit including a charge pump having a plurality of stack-nodes V.sub.CXM and at least one multiplexor for coupling selected stack-nodes V.sub.CXM to a corresponding comparator circuit configured to output a signal indicative of a difference between a selected input to the multiplexor and a reference signal. The number of comparator circuits is less than (N1)M, where N is the conversion gain of the power converter circuit (i.e., the number of charge pump stages X plus one), and M is the number of parallel charge pump legs. Related methods include measuring voltages at stack-nodes V.sub.CXM in a charge pump, wherein the stack-nodes V.sub.CXM are selected by means of a multiplexor and an input to a comparator.