Abstract: An impedance sensing circuit includes three impedance elements and a sensing element arranged in a bridge configuration. A first input terminal is coupled to two of the impedance elements to apply a stimulus signal. In a mutual-sensing mode, a second input terminal is coupled to the third impedance element and the sensing impedance element to apply an opposite phase stimulus signal. The impedance sensing circuit may be configured in a self-sensing mode, in which the opposite phase stimulus signal is decoupled from the third impedance element and the sensing impedance element. At least one of the impedance elements is variable and may be adjusted to balance an offset impedance load on the sensing element.

Abstract: An impedance sensing circuit includes three impedance elements and a sensing element arranged in a bridge configuration. A first input terminal is coupled to two of the impedance elements to apply a stimulus signal. In a mutual-sensing mode, a second input terminal is coupled to the third impedance element and the sensing impedance element to apply an opposite phase stimulus signal. The impedance sensing circuit may be configured in a self-sensing mode, in which the opposite phase stimulus signal is decoupled from the third impedance element and the sensing impedance element. At least one of the impedance elements is variable and may be adjusted to balance an offset impedance load on the sensing element.

Abstract: An impedance sensing circuit includes three impedance elements and a sensing element arranged in a bridge configuration. A first input terminal is coupled to two of the impedance elements to apply a stimulus signal. In a mutual-sensing mode, a second input terminal is coupled to the third impedance element and the sensing impedance element to apply an opposite phase stimulus signal. The impedance sensing circuit may be configured in a self-sensing mode, in which the opposite phase stimulus signal is decoupled from the third impedance element and the sensing impedance element. At least one of the impedance elements is variable and may be adjusted to balance an offset impedance load on the sensing element.

Abstract: An electrical circuit includes a sensor configured to generate a current signal comprising a first portion comprising a contribution from a target source and/or a second portion comprising a contribution from sources other than the target source, a trans-impedance amplifier that amplifies the current signal and generate a low noise signal, and a high pass filter that converts the low noise signal into an AC signal having a positive amplitude, a negative amplitude, and a zero cross-over point between the positive and negative amplitudes. The circuit also includes a positive integrating amplifier that receives the positive amplitude of the AC signal and generates a positive integrated value over an integration period, and a negative integrating amplifier that receives the negative amplitude of the AC signal and generates a negative integrated value over the integration period. The circuit further includes at least one analog-to-digital converter that receives the integrated values.

Abstract: A current detection module capable of differentiating and quantifying contribution to a current signal generated by a sensor in response to stimulation by a certain target source from contributions from sources other than the target source (ambient sources) is disclosed. As long as the contribution from the target source comprises a pulsed signal, the module may synchronize itself to the pulse(s) so that there is a predetermined phase relationship between the pulse(s) and functions carried out by various stages of the module. The module may be re-used to also detect and quantify contributions from ambient sources by presenting these contributions to the module as pulses that trigger synchronization of the module. To that end, a detection system disclosed herein is based on the use of such current detection module and allows mode switching where, depending on the selected mode of operation, the module is configured to perform different measurements.

Abstract: Present disclosure relates to a current detection module capable of differentiating and quantifying contribution to a current signal generated by a sensor in response to stimulation by a certain target source from contributions from sources other than the target source (ambient sources). As long as the contribution from the target source comprises a pulsed signal, the module synchronizes itself to the pulse(s) so that there is a predetermined phase relationship between the pulse(s) and functions carried out by various stages of the module. The module may be re-used to also detect and quantify contributions from ambient sources by presenting these contributions to the module as pulses that trigger synchronization of the module. To that end, a detection system disclosed herein is based on the use of such current detection module and allows mode switching where, depending on the selected mode of operation, the module is configured to perform different measurements.

Abstract: An electrical circuit includes a sensor configured to generate a current signal comprising a first portion comprising a contribution from a target source and/or a second portion comprising a contribution from sources other than the target source, a trans-impedance amplifier that amplifies the current signal and generate a low noise signal, and a high pass filter that converts the low noise signal into an AC signal having a positive amplitude, a negative amplitude, and a zero cross-over point between the positive and negative amplitudes. The circuit also includes a positive integrating amplifier that receives the positive amplitude of the AC signal and generates a positive integrated value over an integration period, and a negative integrating amplifier that receives the negative amplitude of the AC signal and generates a negative integrated value over the integration period. The circuit further includes at least one analog-to-digital converter that receives the integrated values.

Abstract: An electrical circuit includes a photodiode that receives a light signal from a light source and generates a photocurrent signal, a trans-impedance amplifier that amplifies the photocurrent signal and generates a low noise signal, and a high pass filter that converts the low noise signal into an alternating current (AC) signal having a positive amplitude, a negative amplitude, and a zero cross-over point between the positive amplitude and the negative amplitude. The electrical circuit also includes a positive integrating amplifier that receives the positive amplitude of the AC signal and generates a positive integrated value over an integration period, and a negative integrating amplifier that receives the negative amplitude of the AC signal and generates a negative integrated value over the integration period. The electrical circuit further includes at least one analog-to-digital converter that receives the positive and negative integrated values.

Abstract: An electrical circuit includes a photodiode that receives a light signal from a light source and generates a photocurrent signal, a trans-impedance amplifier that amplifies the photocurrent signal and generates a low noise signal, and a high pass filter that converts the low noise signal into an alternating current (AC) signal having a positive amplitude, a negative amplitude, and a zero cross-over point between the positive amplitude and the negative amplitude. The electrical circuit also includes a positive integrating amplifier that receives the positive amplitude of the AC signal and generates a positive integrated value over an integration period, and a negative integrating amplifier that receives the negative amplitude of the AC signal and generates a negative integrated value over the integration period. The electrical circuit further includes at least one analog-to-digital converter that receives the positive and negative integrated values.

Abstract: Embodiments of the present invention employ a charged-based readout circuit in an image sensing system that includes a column readout circuit which may perform sampling on signals received from a pixel array and transfer a corresponding correlated double sample (CDS) signal, a differential channel readout circuit that may receive the corresponding CDS signal and amplify the signal using an output amplifier, and an output buffer which may receive the amplified CDS signal and output a corresponding signal out of the system. The output amplifier may be composed of two output amplifier paths so that ping-ponging is possible.

Abstract: A current detection module capable of differentiating and quantifying contribution to a current signal generated by a sensor in response to stimulation by a certain target source from contributions from sources other than the target source (ambient sources) is disclosed. As long as the contribution from the target source comprises a pulsed signal, the module may synchronize itself to the pulse(s) so that there is a predetermined phase relationship between the pulse(s) and functions carried out by various stages of the module. The module may be re-used to also detect and quantify contributions from ambient sources by presenting these contributions to the module as pulses that trigger synchronization of the module. To that end, a detection system disclosed herein is based on the use of such current detection module and allows mode switching where, depending on the selected mode of operation, the module is configured to perform different measurements.