An apparatus and associated method are provided involving one or more registers configured to store a plurality of values including a first value corresponding with a first capacitance, and a second value corresponding with a second capacitance. Further included is a decoder configured to decode the values into corresponding capacitive settings. Also included is one or more capacitive elements in electrical communication with the decoder. Such one or more capacitive elements are configured to exhibit different capacitances, based on the capacitive settings. Also included is control circuitry in electrical communication with the decoder and the one or more registers. Such control circuitry is configured to control a transition of the capacitance of the one or more capacitive elements from the first capacitance to the second capacitance, by creating a plurality of additional values between the first value and the second value for being decoded by the decoder.

A method and apparatus for performing a two-point calibration of a VCO in a PLL is disclosed. The method includes determining a first steady state tuning voltage of the VCO with no modulation voltage applied. Thereafter, an iterative process may be performed wherein a modulation voltage is applied to the VCO (along with the tuning voltage) and a modified divisor is applied to the divider circuit in the feedback loop. During each iteration, after the PLL is settled, the tuning voltage is measured and a difference between the current value and the first value is determined. If the current and first values of the turning voltage are not equal, another iteration may be performed, modifying at least one of the modulation voltage and the divisor, and determining the difference between the current and first values of the tuning voltage.

A wireless communication system includes a plurality of wireless sensors. A wireless sensor includes a radio frequency (RF) receiving circuit, and a sensing element, where the sensing element affects the resonant frequency of the RF receiving circuit. The wireless sensor further includes a processing module operable to determine a first value for an adjustable element of a plurality of elements for a known environmental condition, a second value for the adjustable element for an unknown environmental condition, a difference between the first and second values that corresponds to a change, and to generate a coded value representative of the change. The wireless communication system further includes one or more sensor computing devices coupled to the plurality of wireless sensors via a network. A sensor computing device includes a second processing module operable to receive the coded value and determine a sensed environmental condition based on the coded value.

In a first clock frequency multiplier, multiple injection-locked oscillators (ILOs) having spectrally-staggered lock ranges are operated in parallel to effect a collective input frequency range substantially wider than that of a solitary ILO. After each input frequency change, the ILO output clocks may be evaluated according to one or more qualifying criteria to select one of the ILOs as the final clock source. In a second clock frequency multiplier, a flexible-injection-rate injection-locked oscillator locks to super-harmonic, sub-harmonic or at-frequency injection pulses, seamlessly transitioning between the different injection pulse rates to enable a broad input frequency range. The frequency multiplication factor effected by the first and/or second clock frequency multipliers in response to an input clock is determined on the fly and then compared with a programmed (desired) multiplication factor to select between different frequency-divided instances of the frequency-multiplied clock.

A method includes sending, by a reader, a radio frequency (RF) signal to a wireless sensor that includes an antenna having a tail section and a head section. The tail section is for placement in an RF limited area for sensing moisture in a first location of a vehicle under test and wherein the head section is for placement in a non-RF limited area. The method further includes receiving, by the reader, an RF response to the RF signal from the wireless sensor. The first RF response includes an indication of adjustment of one or more RF characteristics of the wireless sensor, which corresponds to a variance of the one or more RF characteristics from a desired value, which, in turn, corresponds to a level of moisture at the first location. The method further includes outputting, by the reader, a message regarding the level of moisture at the first location.

Techniques are described for tuning a resonant circuit using differential switchable capacitors. For example, embodiments can operate in context of a power amplifier with a tunable resonant output network. To tune the network, multiple differential switchable capacitors are provided in parallel. Each differential switchable capacitor can include a pair of capacitors, each coupled between a respective internal node and a respective differential terminal; and the internal nodes are selectively coupled or decoupled using a respective electronic switch (e.g., transistor). Switching on one of the differential switchable capacitors forms a capacitive channel having an associated capacitance. Each differential switchable capacitor can also include a switch network to selectively pull the internal nodes to a high or low voltage reference according to the selected operating mode.

Disclosed is an authentication reader intended to be installed on a motor vehicle opening element, the reader including a microcontroller, at least one transmitter, at least one matching circuit and a single antenna, called primary antenna, characterized by a working frequency. The matching circuit includes switching element able to switch the matching circuit between a first mode, in which the matching circuit makes it possible to match the primary antenna to a secondary antenna of an authentication device whose resonant frequency is lower than the working frequency, and a second mode, in which the matching circuit makes it possible to match the primary antenna to a secondary antenna of an authentication device whose resonant frequency is higher than the working frequency.

[Overview] [Problem to be Solved] To provide a semiconductor device and a wireless communication apparatus each of which makes it possible to suppress the manufacturing cost and the power consumption while maintaining the manual operability. [Solution] There is provided a semiconductor device including: an oscillation circuit including a plurality of capacitors provided on a semiconductor substrate; a conversion circuit that converts an analog signal into a digital signal; and a switch circuit that switches the capacitors on the basis of the digital signal. An oscillation frequency linearly varies with respect to a variation in the analog signal.

Techniques are disclosed implementing a tunable transformer with additional taps in at least one of the three coils. The tunable transformer enables the resonant frequency within RF transceiver matching networks to be adjusted without substantially impacting the output power at resonance. The tunability of the transformer is partially driven by the insertion of additional coils within the transformer, which are selectively switched and may be further coupled with a tunable capacitance. The tunability of the transformer is further driven via the use of at least one multi-tap transformer coil, which allows electronic components to be coupled to different coil taps to thereby facilitate an adjustable DC inductance. Doing so counteracts changes in mutual inductance between the non-switched coils, and facilitates the stabilization of output power with shifts in resonant frequency.

A digitally controlled oscillator (DCO) circuit is disclosed. The DCO circuit comprises a tuning circuit configured to tune an oscillation frequency of the DCO circuit based on processing an integer tuning codeword and a fractional tuning codeword associated with an input tuning codeword. In some embodiments, the tuning circuit comprises an integer tuning circuit configured to process the integer tuning codeword and a fractional tuning circuit configured to process the fractional tuning codeword, in order to implement the input tuning codeword. In some embodiments, the integer tuning codeword comprises an integer tuning range associated therewith and the fractional tuning codeword comprises a fractional tuning range associated therewith. In some embodiments, the fractional tuning range associated with the fractional tuning codeword is configured to cover more than one step of the integer tuning range associated with the integer tuning codeword.