摘要:
A direct digital synthesis circuit (108) includes a plurality of current sources (210, 211, 212), an output circuit (200), and a logical multiplier circuit (202). The output circuit (200) provides a synthesized waveform (164) output and includes a first (206) and second branch (208). The logical multiplier circuit (202) is operatively coupled to the plurality of current sources (210, 211, 212) and to the output circuit (200). The logical multiplier circuit (202) is operative to receive a plurality of signals. The logical multiplier circuit is also operative to selectively increase a first current flow through the first branch (206) by a determined magnitude and decrease a second current flow through the second branch (208) by the determined magnitude based on the plurality of signals. The synthesized waveform (164) is based on the first and second currents.
摘要:
A radio frequency identification exciter (200) includes a plurality of antenna elements (122a-i) that are spaced to define active areas (130a-e). A matrix switch (202) flexibly connects the plurality of antenna elements to an exciter circuit (203). Independent switches (204a-i) are selectively switched such that an electric field is generated between at least two antenna elements whereby radio frequency identification tags (132) in the vicinity of the two antenna elements are capacitively powered to exchange data with the exciter. Antenna elements other than the at least two antenna elements may be selectively coupled to a signal from the exciter circuit that inhibits activation of radio frequency identification tags in the vicinity of those antenna elements. The matrix switch preferably comprises polymer-based circuits.
摘要:
A capacitively powered radio frequency identification device (10) comprises a substrate (12), a conductive pattern (14, 16) and a circuit (18). The substrate (12) has a first surface and a second surface. The conductive pattern is formed on the first surface of the substrate (12). The conductive pattern has a first electrode (14) and a second electrode (16). The first and second electrodes (14, 16) are isolated from each other by a non-conductive region disposed therebetween. The circuit (18) comprises polymers. The circuit (18) is electrically coupled to the first electrode (14) and the second electrode (16).
摘要:
A common-mode sensing circuit (504) of a clocked differential amplifier (602) includes a refresh circuit (604) which precharges a capacitance during a first clock phase (P.sub.1) and discharges the capacitance to drive the outputs (514, 516) of the differential amplifier (602) to a desired common-mode voltage (V.sub.AGO) during a second clock phase, which increases the output loading during the second clock phase (P.sub.2). A load balancing circuit (606) selectively switches a load to the outputs (514, 516) during the first clock phase (P.sub.1) to match the load produced by the refresh circuit (604) during the second clock phase (P.sub.2).
摘要:
A non-inverting, inverting, delayed non-inverting, and delayed inverting non-overlapping clock signal is provided by a non-overlapping clock generator circuit (41, 61). The non-overlapping clock generator circuit (41, 61) increases time for circuit operation by minimizing delays between non-overlapping clock signals and simultaneously transitioning rising edges of clock signals. A non-overlapping clock generation circuit (41) comprises six NOR gates (43-48) and an inverter (42). Three NOR gates form a first delay line (43-45) and the remaining three NOR gates form a second delay line (46-48). The inverter (42) provides an inverted clock signal to the second delay line. A clock signal propagates through one delay line while the other delay line is non-responsive due to a feedback signal from the active delay line. Once the clock signal has propagated through the active delay line, the feedback signal changes and allows NOR gates of the remaining delay line to simultaneously provide a clock signal and a delayed clock signal.
摘要:
A switched capacitor gain stage (21) that samples an input voltage every clock cycle phase for effectively doubling the frequency of operation. The switched capacitor gain stage (21) comprising an amplifier (22), a first capacitor network, and a second capacitor network. Either the first or second capacitor network is sampling an input voltage. For example, the first capacitor network samples an input voltage. Capacitors of the first capacitor network are coupled to sample the input voltage via switches. Capacitors of the second switched capacitor network are coupled around the amplifier (22) in a gain configuration via switches. The capacitors of the second switched capacitor network having a voltage stored from a previous clock phase. In a next clock phase the second switched capacitor network are coupled via switches for sampling an input voltage and the first switched capacitor network is coupled via switches in a gain configuration around the amplifier (22).
摘要:
A shield for differential transmission lines formed in a first metal layer may include one or more floating shields, each floating shield comprising an upper-side tile formed in a second metal layer of the integrated circuit adjacent to the first metal layer, a lower-side tile formed in a third metal layer of the integrated circuit adjacent to the first metal layer and non-adjacent to the second metal layer, and at least one via configured to electrically couple the upper-side tile at an end of the length of the upper-side tile to the lower-side tile and at an end of the length of the lower-side tile.
摘要:
A shield for differential transmission lines formed in a first metal layer may include one or more floating shields, each floating shield comprising an upper-side tile formed in a second metal layer of the integrated circuit adjacent to the first metal layer, a lower-side tile formed in a third metal layer of the integrated circuit adjacent to the first metal layer and non-adjacent to the second metal layer, and at least one via configured to electrically couple the upper-side tile at an end of the length of the upper-side tile to the lower-side tile and at an end of the length of the lower-side tile.
摘要:
In accordance with embodiments of the present disclosure, a continuous-time incremental analog-to-digital converter (ADC) may include a plurality of resettable integrators and a feed-in gain element. Each integrator may be configured to convert a sum of signals received at its input to a signal indicative of an integral over time of the sum of signals. The plurality of integrators may include a first-stage integrator configured to receive at its input the baseband signal and a final-stage integrator configured to produce at its output a final-stage analog signal. The plurality of integrators may be arranged in a cascade configuration such that an output of each of the plurality of integrators other than the final-stage integrator is coupled to the input of a subsequent integrator. The feed-in gain element may be coupled between the input of the first-stage integrator and the input of another integrator of the plurality of integrators.
摘要:
In accordance with some embodiments of the present disclosure, a multi-band transmitter comprises a plurality of band paths with each band path configured for a different frequency range. Each band path comprises a modulator configured to modulate a data signal onto a carrier signal associated with the frequency range of the band path to generate a radio frequency (RF) signal associated with the band path and frequency range of the band path. Each band path also comprises a step-down balun that includes an input coil configured to receive the RF signal from the modulator. Each band path further comprises a tuner configured to tune the input coil to the frequency range of the band path. The tuner is also configured to compensate for off-state conduction of switches of the tuner to reduce non-linear tuning effects of the balun associated with the off-state conduction.