Systems and techniques relating to voltage signal peak level detection used in sensor devices, namely in Fly-Height Sensors (FHS) devices include, according to an aspect, an integrated chip device comprising: peak detection circuitry configured to receive a voltage signal and output a peak voltage signal associated with a peak voltage level of the voltage signal, wherein the peak detection circuitry comprises: a linear loop section configured to store the peak voltage level and hold additional voltage levels of the voltage signal at an output terminal of an amplifier to a value greater than zero; and a feedback loop section configured to reduce a leakage current within the peak detection circuitry and generate a guard voltage signal usable to reduce a feedback voltage and prevent the feedback voltage from successively re-entering into the feedback loop section.

A first inductive loop is formed within a printed circuit board (PCB). The PCB is mounted in a fixed spatial relationship with a radiofrequency power supply structure. A second inductive loop is formed within the PCB. The second inductive loop is positioned in fixed spatial relationship with the first inductive loop such that a distance between the centerpoints of the first and second inductive loops has a fixed value and is precisely known. Each of the first and second inductive loops is formed in an essentially identical manner with regard to number of complete turns of the loops and a size of the loops. A first voltage signal present on the first inductive loop and a second voltage signal present on the second inductive loop and the distance between the first and second loops provide for determination of a radiofrequency current present on the radiofrequency power supply structure.

An apparatus and method thereof are described to measure alternating current (AC) power, including: an AC voltage measurement circuit, an in-phase/quadrature (I/Q) direct down converter, an analog/digital converter, and an AC power calculator. The AC voltage measurement circuit is configured to measure first and second AC positive voltages and first and second AC negative voltages from an AC voltage source. The I/Q direct down converter is configured to directly convert each of the first and second AC positive voltages and the first and second AC negative voltages into an I-signal and a Q-signal orthogonal to each other using down conversion. The analog/digital converter is configured to convert the I-signal and the Q-signal into I-data and Q-data, respectively. The AC power calculator is configured to calculate the AC power using the I-data and the Q-data.

A radio frequency (RF) power detector includes a first circuit having a first rectifying diode with a first terminal coupled to a first power supply voltage node. The first circuit also includes an input terminal coupled to a second terminal of the first rectifying diode, a first transistor having a first collector coupled to the second terminal of the first rectifying diode and a first emitter coupled to a reference voltage node, and a second transistor having a second emitter coupled to the reference voltage node and a second collector coupled to a second power supply voltage node. The first circuit further includes a low-pass filter network coupled between a first base of the first collector and a second base of the second transistor, and a first output terminal coupled to the second collector of the second transistor.

An RF peak-detector circuit can operate over a wide range and can compensate or correct an output voltage error term that depends on the thermal voltage and the input signal voltage. At or near a minimum value of the input signal voltage range, such compensation can include a scaled base-emitter ratioing of bipolar junction transistors used to generate the output voltage, each of which can be biased by a primary current. At or near a maximum value of the input signal voltage range, this can include using an auxiliary bias current circuit that can shift auxiliary bias current between these bipolar junction transistors. The auxiliary bias current circuit can include scaled bipolar junction transistors in a cross-coupled configuration and an equivalent resistance circuit between emitters of the cross-coupled BJTs. This can provide a robust approach for improving the accuracy of an RF peak-detector circuit over a wide range.

An RF peak-detector circuit can operate over a wide range and can compensate or correct an output voltage error term that depends on the thermal voltage and the input signal voltage. At or near a minimum value of the input signal voltage range, such compensation can include a scaled base-emitter ratioing of bipolar junction transistors used to generate the output voltage, each of which can be biased by a primary current. At or near a maximum value of the input signal voltage range, this can include using an auxiliary bias current circuit that can shift auxiliary bias current between these bipolar junction transistors. The auxiliary bias current circuit can include scaled bipolar junction transistors in a cross-coupled configuration and an equivalent resistance circuit between emitters of the cross-coupled BJTs. This can provide a robust approach for improving the accuracy of an RF peak-detector circuit over a wide range.

An RF peak-detector circuit can operate over a wide range and can compensate or correct an output voltage error term that depends on the thermal voltage and the input signal voltage. At or near a minimum value of the input signal voltage range, such compensation can include a scaled base-emitter ratioing of bipolar junction transistors used to generate the output voltage, each of which can be biased by a primary current. At or near a maximum value of the input signal voltage range, this can include using an auxiliary bias current circuit that can shift auxiliary bias current between these bipolar junction transistors. The auxiliary bias current circuit can include scaled bipolar junction transistors in a cross-coupled configuration and an equivalent resistance circuit between emitters of the cross-coupled BJTs. This can provide a robust approach for improving the accuracy of an RF peak-detector circuit over a wide range.

An apparatus and method for lost power detection are described. In one implementation, an apparatus for wirelessly transferring power comprises a wireless power transmitter configured to wirelessly transmit power at a first power level sufficient to power or charge a chargeable device. The apparatus further comprises a controller configured to obtain a first power measurement of the first power level. The controller is further configured to determine a first adjusted power measurement of the first power measurement based on one or more tolerance values of the wireless power transmitter. The controller is further configured to determine a second adjusted power measurement of a second power measurement of a second power level received by the chargeable device based on one or more tolerance values of the chargeable device. The controller is further configured to determine if a power difference between the first and second adjusted power measurements exceeds a threshold value.

An apparatus and method for lost power detection are described. In one implementation, an apparatus for wirelessly transferring power comprises a wireless power transmitter configured to wirelessly transmit power at a first power level sufficient to power or charge a chargeable device. The apparatus further comprises a controller configured to obtain a first power measurement of the first power level. The controller is further configured to determine a first adjusted power measurement of the first power measurement based on one or more tolerance values of the wireless power transmitter. The controller is further configured to determine a second adjusted power measurement of a second power measurement of a second power level received by the chargeable device based on one or more tolerance values of the chargeable device. The controller is further configured to determine if a power difference between the first and second adjusted power measurements exceeds a threshold value.

On a tablet user equipment that is proximate to a hand phantom, a method determines the total radiated power of the user equipment includes, in response to a preset criterion, obtains a characteristic of the phantom, obtains a characteristic of an antenna of the user equipment, and obtains a radio characteristic of the user equipment. The method may also include transmitting the phantom characteristic, the antenna characteristic, and the radio characteristic to a test equipment.