A metering circuit includes a comparator including a first input to receive an input signal, and including a second input and an output. The metering circuit further includes a reference source to provide a time-varying reference signal to the second input during a peak counting operation.

Methods and apparatuses for sensing biological functions are disclosed. Sensors can be implanted in an organ, such as the brain, and a magnetic field gradient applied to the biological tissue. The field causes the sensors to have different resonant frequencies allowing their spatial localization. The sensors can harvest power from the external coils to be able to retransmit data.

A power-supply voltage sensing device is disclosed, which relates to a technology for detecting a level of an external power-supply voltage during a test mode. The power-supply voltage sensing device includes a reference voltage trimming unit configured to trim a reference voltage in response to a code signal, a power-supply voltage detection unit configured to select one of a power-supply voltage and an external power-supply voltage in response to a test signal, compare the external power-supply voltage with the reference voltage, and output a detection signal according to the result of comparison, and a reference voltage control unit configured to output the code signal in response to the detection signal.

A power-supply voltage sensing device is disclosed, which relates to a technology for detecting a level of an external power-supply voltage during a test mode. The power-supply voltage sensing device includes a reference voltage trimming unit configured to trim a reference voltage in response to a code signal, a power-supply voltage detection unit configured to select one of a power-supply voltage and an external power-supply voltage in response to a test signal, compare the external power-supply voltage with the reference voltage, and output a detection signal according to the result of comparison, and a reference voltage control unit configured to output the code signal in response to the detection signal.

Disclosed are methods, systems, apparatuses and computer programs for estimating a measure of the gain and offset of a converter that generates, based on digital settings, reference voltages to be used as thresholds by a comparator in a photon-counting detector in an x-ray imaging system. Steps include selecting a first converter as a reference converter and a second converter as a target converter; assigning different digital settings to the reference converter to generate at least two different reference voltages to be used as thresholds by a comparator associated with the reference converter; and obtaining, based on photon count measurements, the number of photons registered in a photon counter associated with a comparator whose reference voltage is generated by the target converter. Based on the number of photons and the at least two digital settings, an estimate of the gain and offset of the target converter relative the reference converter results.

Disclosed are methods, systems, apparatuses and computer programs for estimating a measure of the gain and offset of a converter that generates, based on digital settings, reference voltages to be used as thresholds by a comparator in a photon-counting detector in an x-ray imaging system. Steps include selecting a first converter as a reference converter and a second converter as a target converter; assigning different digital settings to the reference converter to generate at least two different reference voltages to be used as thresholds by a comparator associated with the reference converter; and obtaining, based on photon count measurements, the number of photons registered in a photon counter associated with a comparator whose reference voltage is generated by the target converter. Based on the number of photons and the at least two digital settings, an estimate of the gain and offset of the target converter relative the reference converter results.

Disclosed are methods, systems, apparatuses and computer programs for estimating a measure of the gain and offset of a converter that generates, based on digital settings, reference voltages to be used as thresholds by a comparator in a photon-counting detector in an x-ray imaging system. Steps include selecting a first converter as a reference converter and a second converter as a target converter; assigning different digital settings to the reference converter to generate at least two different reference voltages to be used as thresholds by a comparator associated with the reference converter; and obtaining, based on photon count measurements, the number of photons registered in a photon counter associated with a comparator whose reference voltage is generated by the target converter. Based on the number of photons and the at least two digital settings, an estimate of the gain and offset of the target converter relative the reference converter results.

Disclosed are methods, systems, apparatuses and computer programs for estimating a measure of the gain and offset of a converter that generates, based on digital settings, reference voltages to be used as thresholds by a comparator in a photon-counting detector in an x-ray imaging system. Steps include selecting a first converter as a reference converter and a second converter as a target converter; assigning different digital settings to the reference converter to generate at least two different reference voltages to be used as thresholds by a comparator associated with the reference converter; and obtaining, based on photon count measurements, the number of photons registered in a photon counter associated with a comparator whose reference voltage is generated by the target converter. Based on the number of photons and the at least two digital settings, an estimate of the gain and offset of the target converter relative the reference converter results.

According to one aspect, embodiments herein provide a system for monitoring circuit branches coupled to an input line of a load center, the system comprising a plurality of first current sensors, each configured to be coupled to a circuit branch, at least one second current sensor configured to be coupled to the input line, a controller, a plurality of first sensor circuits, each configured, in a first mode of operation, to sample a signal from an associated current sensor, and in a second mode of operation, to be powered off, and at least one second sensor circuit configured to sample a signal from the at least one second current sensor and provide an input line current measurement signal to the controller, wherein the controller is configured to operate each first sensor circuit in one of the first and second modes of operation based on the input line current measurement signal.

According to one aspect, embodiments herein provide a system for monitoring circuit branches coupled to an input line of a load center, the system comprising a plurality of first current sensors, each configured to be coupled to a circuit branch, at least one second current sensor configured to be coupled to the input line, a controller, a plurality of first sensor circuits, each configured, in a first mode of operation, to sample a signal from an associated current sensor, and in a second mode of operation, to be powered off, and at least one second sensor circuit configured to sample a signal from the at least one second current sensor and provide an input line current measurement signal to the controller, wherein the controller is configured to operate each first sensor circuit in one of the first and second modes of operation based on the input line current measurement signal.