Patent classifications
H03M1/66
OFFSET COMPENSATION CIRCUIT FOR A TRACKING LOOP
An offset compensation circuit comprises an error signal generation block arranged for receiving an input phase and an output phase, and for generating an error signal indicative of an error between the input phase and the output phase. Means are provided for combining the error signal with an offset compensation signal, yielding an offset compensated signal. A loop filter is arranged for receiving the offset compensated signal and for outputting the output phase. An offset compensation block is arranged for receiving the output phase and for determining the offset compensation signal. The offset compensation signal comprises at least a contribution proportional to a periodic function of the output phase.
Electromagnetic flow sensor interface allowing dc coupling
An interface circuit to an electromagnetic flow sensor is described. In an example, it can provide a DC coupled signal path from the electromagnetic flow sensor to an analog-to-digital converter (ADC) circuit. Examples with differential and pseudo-differential signal paths are described. Examples providing DC offset or low frequency noise compensation or cancellation are described. High input impedance examples are described. Coil excitation circuits are described, such as can provide on-chip inductive isolation between signal inputs and signal outputs. A switched mode power supply can be used to actively manage a bias voltage of an H-Bridge, such as to boost the current provided by the H-Bridge to the sensor coil during select time periods, such as during phase shift time periods of the coil, which can help reduce or minimize transient noise during such time periods.
Electromagnetic flow sensor interface allowing dc coupling
An interface circuit to an electromagnetic flow sensor is described. In an example, it can provide a DC coupled signal path from the electromagnetic flow sensor to an analog-to-digital converter (ADC) circuit. Examples with differential and pseudo-differential signal paths are described. Examples providing DC offset or low frequency noise compensation or cancellation are described. High input impedance examples are described. Coil excitation circuits are described, such as can provide on-chip inductive isolation between signal inputs and signal outputs. A switched mode power supply can be used to actively manage a bias voltage of an H-Bridge, such as to boost the current provided by the H-Bridge to the sensor coil during select time periods, such as during phase shift time periods of the coil, which can help reduce or minimize transient noise during such time periods.
Digital-to-analog converter circuit, corresponding device and method
In some embodiments, a circuit for use in devices involving digital-to-analog conversion of signals includes: a capacitive digital-to-analog converter array and an amplifier. The capacitive digital-to-analog converter includes an input port for receiving a digital input signal and an output port. The amplifier includes capacitive feedback loops that include a first capacitor coupling the output of the amplifier with the input of the amplifier and a second capacitor coupled to the output port of the digital-to-analog converter array at the input of the amplifier. The circuit further includes a set of switches that include a first switch and a second switch coupled with opposed ends of the second capacitor at the input and at the output of the amplifier, respectively.
CURRENT STEERING DIGITAL-TO-ANALOG CONVERTER AND INTEGRATED CIRCUIT INCLUDING THE SAME
A current steering digital-to-analog converter includes a plurality of current cells each including a current source circuit and a current switch circuit to selectively output a current in response to a first input signal corresponding to a digital signal; a dummy current cell including a dummy current source circuit and a dummy current switch circuit to output a current in response to a second input signal; and a current switch bias circuit coupled to the dummy current cell to track a first voltage of an internal node of the dummy current source circuit and configured to generate a first bias voltage applied to the current switch circuit.
POWER EFFICIENT TRANSFORMER-BASED INTERFACE CIRCUIT TO INTERFACE A DIFFERENTIAL CURRENT SINKING DAC TO LASER ANODE
An interface circuit that interfaces a digital-to-analog converter (DAC) to a vertical-cavity surface emitting laser. The apparatus includes a first cascode amplifier that receives as input positive and negative differential outputs of the DAC and provides a positive amplified output and a negative amplified output, and a second cascode amplifier having a positive input and a negative input. The positive input of the second cascode amplifier being coupled to the positive amplified output of the first cascode amplifier. The second cascode amplifier is configured to generate a positive amplified current and a negative amplified current at a negative amplified output. The positive amplified current and the negative amplified current are combined and a resulting output current is provided as input to an anode of the laser. A transformer is coupled between the negative amplified output of the first cascode amplifier and the negative input of the second cascode amplifier.
POWER EFFICIENT TRANSFORMER-BASED INTERFACE CIRCUIT TO INTERFACE A DIFFERENTIAL CURRENT SINKING DAC TO LASER ANODE
An interface circuit that interfaces a digital-to-analog converter (DAC) to a vertical-cavity surface emitting laser. The apparatus includes a first cascode amplifier that receives as input positive and negative differential outputs of the DAC and provides a positive amplified output and a negative amplified output, and a second cascode amplifier having a positive input and a negative input. The positive input of the second cascode amplifier being coupled to the positive amplified output of the first cascode amplifier. The second cascode amplifier is configured to generate a positive amplified current and a negative amplified current at a negative amplified output. The positive amplified current and the negative amplified current are combined and a resulting output current is provided as input to an anode of the laser. A transformer is coupled between the negative amplified output of the first cascode amplifier and the negative input of the second cascode amplifier.
METHOD AND APPARATUS FOR CANCELLING FRONT-END DISTORTION
Transceiver circuitry in an integrated circuit device includes a receive path including an analog front end for receiving analog signals from an analog transmission path and conditioning the analog signals, and an analog-to-digital converter configured to convert the conditioned analog signals into received digital signals for delivery to functional circuitry, and a transmit path including a digital front end configured to accept digital signals from the functional circuitry and to condition the accepted digital signals, and a digital-to-analog converter configured to convert the conditioned digital signals into analog signals for transmission onto the analog transmission path. At least one of the analog front end and the digital front end introduces distortion and outputs a distorted conditioned signal. The transceiver circuitry further includes distortion correction circuitry at the one of the analog front end and the digital front end, to determine and apply a distortion cancellation function to the distorted signal.
FORCE SENSING SYSTEMS
The present disclosure relates to a compensation circuit for compensating for an offset voltage that is present in an output signal output by a force sensor. The compensation circuit comprises: voltage divider circuitry, the voltage divider circuitry configured to receive a bias voltage that is also supplied to the force sensor and to output a control voltage derived from the bias voltage, wherein a component mismatch ratio of the voltage divider circuitry is adjustable to correspond to a component mismatch ratio of the force sensor; current generator circuitry configured to receive the control voltage and to generate a compensating current based on the received control voltage; and amplifier circuitry configured to receive the differential signal output by the force sensor and the compensating current and to output a compensated differential output signal in which the offset voltage is at least partially cancelled.
PHASE SHIFTER, DRIVING METHOD FOR THE PHASE SHIFTER AND ANTENNA SYSTEM
The present disclosure provides a phase shifter, a driving method for the phase shifter, and an antenna system, and belongs to the field of communication technologies. The present disclosure provides a phase shifter, including: a control module, a digital-to-analog conversion module and a phase shift structure; the control module is configured to generate a plurality of correction signals according to phase shift degrees of the phase shift structure; the digital-to-analog conversion module is configured to generate a driving signal according to the correction signals; and the phase shift structure is configured to shift a phase of a microwave signal passing therethrough according to the driving signal.