H03M1/00

Adaptively controlled duty cycle clock generation circuit
09838029 · 2017-12-05 · ·

A clock generation circuit coupled to an integrator circuit uses a variable resistance that is adjusted in a transconductance bias feedback circuit. This resistance is calibrated to the reciprocal of the transconductance of the input amplifier. The product of the adjusted resistance and a capacitance in the clock generation circuit provides a time constant for the settling time of the integrator and controls a pulse width of an adaptively controlled duty cycle output clock.

Differential voltage-mode integrate and dump photonic analog to digital converter (pADC)
09835931 · 2017-12-05 · ·

A voltage-mode integrate-and-dump photonic ADC front-end circuit includes a current integrator for immediately integrating current pulses onto a capacitor voltage, the current pulses converted by photodetectors from optical data pulses corresponding to a received analog input signal. The circuit may include dampeners for reducing voltage ringing and resulting intersymbol interference (ISI) to preserve SNR at high data rates. The integrating capacitor may be discharged by a reset switch based on clock signals generated by a master clock; the reset switch may include a pulse width controller enabling the integrating capacitor to track and hold the integrated voltage, rather than downstream sample-and-hold amplifiers. Quantizers and other signal processors generate digital signal output by sampling and digitizing the integrated voltage output of the current integrator.

Noise reduction circuit and associated delta-sigma modulator
09831892 · 2017-11-28 · ·

A circuit includes a transistor, a signal generating circuit and a noise sensing circuit. The signal generating circuit is arranged to provide an input signal. The noise sensing circuit is coupled to the transistor and the signal generating circuit, and the noise sensing circuit is arranged for receiving the input signal provided by the signal generating circuit to generate an output signal to the transistor, wherein a signal component of the output signal generated by the noise sensing circuit cancels out a signal component of the input signal provided by the signal generating circuit, and the output signal and the input signal have opposite polarities.

ANALOG-TO-DIGITAL CONVERTERS

An embodiment includes an analog-to-digital converter device. A device may include a first track and hold amplifier configured to receive an analog input signal. The device may also include a plurality of paths coupled to an output of the first track and hold amplifier. Each path of the plurality of paths includes a second track and hold amplifier coupled to the first track and hold amplifier, and a successive approximation register analog-to-digital converter coupled to an output of the second track and hold amplifier. The successive-approximation analog-to-digital converter may include heterojunction bipolar transistors, a comparator, R-2R DAC, and a SiGe BiCMOS quasi-CML SAR register and sequencer.

Control of a time-interleaved analog-to-digital converter

The disclosure concerns controlling circuitry operably connectable to a plurality of constituent analog-to-digital converters (sub-ADCs) of an asynchronous time-interleaved analog-to-digital converter (TI-ADC). The controlling circuitry is configured to maintain a set of a number of sub-ADCs currently available for processing of an input sample, wherein the set is a subset of the plurality. Maintenance of the set is achieved by reception, from each of one or more of the sub-ADCs of the plurality, of an availability signal indicative of availability of the corresponding sub-ADC, and (responsive to the reception of the availability signal) addition of the corresponding sub-ADC to the set. Maintenance of the set is further achieved by (for each new input sample) selection of a sub-ADC of the set for processing of the new input sample, and (responsive to the selection) removal of the selected sub-ADC from the set and causing of the selected sub-ADC to process the new input sample. Corresponding TI-ADC, wireless communication receiver, wireless communication node, method and computer program product are also disclosed.

Using a sampling switch for multiple evaluation units

In some examples, an integrated circuit device includes a sampling switch configured to sample an input signal. The integrated circuit device also includes a first evaluation unit configured to receive the sampled input signal from the sampling switch and evaluate the sampled input signal. The integrated circuit device further includes a second evaluation unit configured to receive the sampled input signal from the sampling switch and evaluate the sampled input signal. The sampling switch is configured to deliver the sampled input signal to the first evaluation unit and deliver the sampled input signal to the second evaluation unit.

Waveform synthesizer using multiple digital-to-analog converters

A circuit includes a phase-locked loop having a phase-locked loop output to provide a first phase signal and a second phase signal phase delayed with respect to the first phase signal. The circuit further includes a digital circuit having a digital circuit input and an output. The digital circuit input couples to the phase-locked loop output. On the digital circuit output, the digital circuit is configured to provide a first digital-to-analog converter (DAC) enable signal and a second DAC enable signal. The circuit also includes first and second DACs. The first DAC is coupled to the digital circuit. The first DAC has a first enable input coupled to the digital circuit output to receive the first DAC enable signal. The second DAC is coupled to the digital circuit. The second DAC has a second enable input coupled to the digital circuit output to receive the second DAC enable signal.

Sub-ranging SAR analog-to-digital converter with meta-stability detection and correction circuitry
09813073 · 2017-11-07 · ·

A sub-ranging SAR ADC has a coarse flash ADC that generates bit values corresponding to MSBs of the digital output value, and a fine SAR ADC that generates bit values corresponding to LSBs of the digital output value. The fine ADC generates successive analog approximation signals for the analog input signal. Meta-stability (MTS) detection circuitry detects a coarse-ADC MTS condition in the coarse ADC if a magnitude of a difference between a current approximation signal and a previous approximation signal is greater than a specified threshold level. A controller controls operations of the sub-ranging ADC to correct for a detected coarse-ADC MTS condition. The MTS detection circuitry includes a positive MTS detector that detects a positive coarse-ADC MTS condition in the coarse ADC and a negative MTS detector that detects a negative coarse-ADC MTS condition in the coarse ADC.

RECEIVER CIRCUITS
20170317860 · 2017-11-02 ·

A receiver circuit comprising: an input terminal configured to receive an input-signal; a feedforward-ADC configured to provide a feedforward-digital-signal based on the input-signal; a feedforward-DAC configured to provide a feedforward-analogue-signal based on the feedforward-digital-signal; a feedforward-subtractor configured to provide an error-signal based on the difference between the feedforward-analogue-signal and the input-signal; an error-LNA configured to provide an amplified-error-signal based on the error-signal; an error-ADC configured to provide a digital-amplified-error-signal based on the amplified-error-signal; a mixer configured to down-convert a signal in a signal path between the input terminal and the error-ADC; and an error-cancellation-block configured to provide an error-cancelled-signal based on a difference between the digital-amplified-error-signal and the feedforward-digital-signal.

ANALOG SYSTEM AND ASSOCIATED METHODS THEREOF
20220060192 · 2022-02-24 ·

Methods and devices are provided for circuits. One device includes an adjustment circuit having an adjustable resistor for modifying a resistance value of a resistive device, the adjustment circuit connected to an adjustment terminal of the resistive device. The resistance value of the adjustable resistor changes, when a voltage or charge on the adjustment terminal of the adjustable resistor is changed. The adjustable resistor is a phase change element with an adjusting terminal to which different voltage values are applied for adjusting a conversion device threshold value.