A confined data communication system includes a reference generation circuit operable to produce one or more analog reference signals, an analog to digital converter circuit operable to process an analog signal to produce a digital representative signal, a digital filtering circuit operable to filter the digital representative signal to produce an affect value, a data processing module operable to interpret the affect value to produce processed output data, and a processing module operable to set frequency and waveform for each of the one or more analog reference signals, set digital filtering parameters for the digital filtering circuit, set a sampling rate for the analog to digital converter circuit, and set data interpretation parameters for the data processing module.

A high resolution analog to digital converter (ADC) with improved bandwidth senses an analog signal (e.g., a load current) to generate a digital signal. The ADC operates based on a load voltage produced based on charging of an element (e.g., a capacitor) by a load current and a digital to analog converter (DAC) output current (e.g., from a N-bit DAC). The ADC generates a digital output signal representative of a difference between the load voltage and a reference voltage. This digital output signal is used directly, or after digital signal processing, to operate an N-bit DAC to generate a DAC output current that tracks the load current. In addition, quantization noise is subtracted from the digital output signal thereby extending the operational bandwidth of the ADC. In certain examples, the operational bandwidth of the ADC extends up to 100s of kHz (e.g., 200-300 kHz), or even higher.

Systems and methods for correction of sigma-delta analog-to-digital converters (ADCs) using neural networks are described. In an illustrative, non-limiting embodiment, a device may include: an ADC; a filter coupled to the ADC, where the filter is configured to receive an output from the ADC and to produce a filtered output; and a neural network coupled to the filter, where the neural network is configured to receive the filtered output and to produce a corrected output.

Aspects of the description provide for an analog-to-digital converter (ADC) operable to convert an analog input signal to an output signal at an output of the ADC. In some examples, the ADC includes multiple sub-ADCs coupled in parallel, each of the multiple sub-ADCs coupled to the output of the ADC and operable to receive the analog input signal. The ADC is configured to operate the sub-ADCs in a consecutive operation loop including a transition phase in which the ADC operates each of the sub-ADCs sequentially for a first number of sequences, an estimation phase in which the ADC operates each of the sub-ADCs sequentially for a second number of sequences following the first number of sequences, and a randomization phase in which the ADC operates subsets of the sub-ADCs for a third number of sequences following the second number of sequences.

A method for differentiator-based compression of digital data includes (a) multiplying a tap-weight vector by an original data vector to generate a predicted signal, the original data vector comprising N sequential samples of an original signal, N being an integer greater than or equal to one, (b) using a subtraction module, subtracting the predicted signal from a sample of the original signal to obtain an error signal, (c) using a quantization module, quantizing the error signal to obtain a quantized error signal, and (d) updating the tap-weight vector according to changing statistical properties of the original signal.

A composite analog-to-digital converter (ADC) has a low resolution ADC configured to receive and digitize analog data, the low resolution ADC having a low resolution and a high operating speed, one or more high resolution ADCs configured to receive and digitize the analog data, the one or more high resolution ADCs having a resolution higher than the low resolution ADC, and an operating speed lower than the high operating speed of the low resolution ADC, a sample clock generator to provide a sample clock signal to the low resolution ADC and to a clock divider, a mixer to receive the analog data and connected to the one or more high resolution ADCs, a local oscillator connected to the mixer to allow the one or more high resolution ADCs to be tuned to sample a portion of a spectrum of the first ADC. A test and measurement instrument contains a composite ADC. A method of operating a composite analog-to-digital converter (ADC), includes receiving an analog signal at a low resolution ADC that operates at a high speed, receiving the analog signal at one or more high resolution ADCs that operate at a resolution higher than the low resolution ADC and at a lower speed than the operating speed of the low resolution ADC, tuning the high resolution ADC to phase align and time align a signal path for the one or more high resolution ADCs to the signal path for the low resolution ADC, producing a spectrum from the low resolution ADC, and producing a portion of the spectrum from the one or more high resolution ADCs.

An analog to digital converter (ADC) that is configured to service a photo-diode includes a capacitor and a self-referenced latched comparator. The capacitor produces a photo-diode voltage based on charging by a photo-diode current associated with the photo-diode and a digital to analog converter (DAC) source current and/or a DAC sink current. The self-referenced latched comparator generates a first digital signal that is based on a difference between the photo-diode voltage and a threshold voltage associated with the self-referenced latched comparator. Also, one or more processing modules executes operational instructions to process the first digital signal to generate a second digital signal and/or a third digital signal. An N-bit DAC generates the DAC source current based on the second digital signal, and an M-bit DAC generates the DAC sink current based on the third digital signal. The DAC source current and/or the DAC sink current tracks the photo-diode current.

An analog to digital conversion circuit includes an analog to digital converter (ADC) circuit operable to convert an analog signal having an oscillation frequency into a first digital signal having a first data rate frequency. The analog signal includes a set of pure tone components. The first digital signal includes n 1-bit channels. The analog to digital conversion circuit further includes a digital decimation filtering circuit including n anti-aliasing filters operable to sample and filter the n 1-bit channels of the first digital signal to produce n second digital signals and n decimator circuits operable to decimate the n second digital signals to produce n third digital signals at a second data rate frequency. The analog to digital conversion circuit further includes a multiplexor operable to output the n third digital signals at the second data rate frequency on a single bus.

A feed forward equalizer including a first set of filter taps having a first set of filter tap coefficients to be adapted and a second set of one or more filter taps having one or more filter tap coefficients to be constrained. The feed forward equalizer includes an adaptation component to determine a set of adapted filter tap coefficient values corresponding to the first set of filter tap coefficients and a constraint function component to determine a constrained filter tap coefficient value for the second set of the one or more filter taps having the one or more filter tap coefficients to be constrained using a constraint function based on at least a portion of the set of adapted filter tap coefficient values. The feed forward equalizer generates, based at least in part on the constrained filter tap coefficient value, an equalized signal including a set of estimated symbol values.

Systems, devices, and methods related to low-noise, high-accuracy single-ended continuous-time sigma-delta (CTSD) analog-to-digital converter (ADC) are provided. An example single-ended CTSD ADC includes a pair of input nodes to receive a single-ended input signal and input circuitry. The input circuitry includes a pair of switches, each coupled to one of the pair of input nodes; and an amplifier to provide a common mode signal at a pair of first nodes, each before one of the pair of switches. The single-ended CTSD ADC further includes digital-to-analog converter (DAC) circuitry; and integrator circuitry coupled to the input circuitry and the DAC circuitry via a pair of second nodes.