A real-time digital sparkle filter for processing high-speed analog to digital converter (ADC) data is disclosed. The real-time digital sparkle filter for processing a continuous stream of digital data, comprising a high-speed data interface, a digital sparkle filter, and a buffer sequencer. The high-speed data interface receives sample data from an analog to digital converter (ADC). The digital sparkle filter operates continuously on the sample data without losing any samples. The digital sparkle filter comprises one or more logic implemented using field-programmable gate arrays (FPGAs) configured to continuously process the data without degrading the signal content. The buffer sequencer comprises an input buffer and an output buffer. The input buffer receives the digital data stream data using a first in first out buffer mechanism. The output buffer receives the processed output of the sparkle filter, thereby eliminating the sparkle noise without degrading data content.

Examples of this description provide for a circuit. In some examples, the circuit includes a resistive network, a least significant bit (LSB) capacitor selectively coupled via a switch to receive an analog input voltage or to a selected first tap in the resistive network, and a charge boost network coupled in parallel with the resistive network and to a midpoint of the resistive network. To determine a most significant bit of lower order bits of a digital representation of the analog input voltage, the charge boost network is coupled to the LSB capacitor.

An analog-to-digital converter (ADC) system includes a main ADC, a reference ADC, a sampling control circuit, and a calibration circuit. The main ADC obtains a first sampled input voltage by sampling an analog input according to a first sampling clock, and performs analog-to-digital conversion upon the first sampled voltage to generate a first sample value. The reference ADC obtains a second sampled voltage by sampling the analog input according to a second sampling clock, and performs analog-to-digital conversion upon the second sampled voltage to generate a second sample value. The sampling control circuit controls the second sampling clock to ensure that the second sampling clock and the first sampling clock have a same frequency but different phases, and adjusts the second sample value to generate a reference sample value. The calibration circuit applies calibration to the main ADC according to the first sample value and the reference sample value.

Disclosed successive approximation register analog-to-digital converters (SAR ADCs) and conversion methods detect a statistical effect of meta-stability induced errors and limit the level of such errors. One illustrative integrated circuit chip includes: a SAR ADC that employs asynchronous bit cycles to convert a sequence of analog signal samples into a sequence of digital signal samples; and a detector that accelerates the asynchronous bit cycles when a meta-stability error bias exceeds a predetermined threshold. An illustrative analog-to-digital conversion method includes: converting a sequence of analog signal samples to a sequence of digital signal samples using a successive approximation register analog to digital converter (SAR ADC) with asynchronous bit cycles; deriving a meta-stability error bias from the sequence of digital signal samples; and accelerating the asynchronous bit cycles when the meta-stability error bias exceeds a predetermined threshold.

A kickback current is suppressed so as not to generate a deviation in a signal that outputs a comparison result.

A comparator includes a first input terminal and a second input terminal to which a first differential input signal pair is input, a third input terminal and a fourth input terminal to which a second differential input signal pair is input, a first comparison circuit that outputs a signal corresponding to a difference signal of the first differential input signal pair generated by connecting the first input terminal to a positive side and connecting the second input terminal to a negative side and a difference signal of the second differential input signal pair generated by connecting the third input terminal to a positive side and connecting the fourth input terminal to a negative side, and a second comparison circuit that outputs a signal corresponding to a difference signal of the first differential input signal pair generated by connecting the first input terminal to a negative side and connecting the second input terminal to a positive side, and a difference signal of the second differential input signal pair generated by connecting the third input terminal to a positive side and connecting the fourth input terminal to a negative side.

Certain aspects of the present disclosure are directed to a radio frequency digital-to-analog converter (RFDAC). The RFDAC generally includes a plurality of digital-to-analog (DAC) unit cells. At least one DAC unit cell is capable of being configured in an active state or in a sleep state. For the at least one DAC unit cell, an output impedance of the DAC unit cell in the active state is equal to an output impedance of the DAC unit cell in the sleep state.

A DAC current steering circuit includes first and second transistors, respectively coupled to first and second outputs via first and second nodes at their drains, and source coupled to each other and to ground. A gate of the first transistor is coupled to a data input (D), and a gate of the second transistor coupled to a complement of the data input (DB). The circuit further includes first and second bleeder transistors, whose drains are respectively coupled to the first and second nodes, and whose sources are coupled together at a third node, the third node coupled to ground, and first and second bleeder switching transistors, whose drains and sources are each coupled to the third node, a gate of the first bleeder switching transistor coupled to a switching input (S) and a gate of the second bleeder switching transistor coupled to a complement of the switching input (SB).

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.

A driver and an electronic device include a capacitor driving circuit and a capacitor circuit having a plurality of capacitors provided between a plurality of capacitor driving nodes and a data voltage output terminal, and the capacitor driving circuit includes a plurality of driving units that output capacitor driving voltages. In the case where the capacitor that has the highest capacitance among the plurality of capacitors is driven, the driving unit that drives that highest capacitor is a driving unit whose driving capability is variable.

A method of enhancing SAR ADC conversion rate by employing a new value shifted capacitor DAC. The value shifted capacitor DAC decreases largest capacitor to improve the reference voltage settling. The reduction of capacitor is added back onto the smaller capacitor DAC to maintain the same total capacitor value. The binary search outputs are re-combined and processed to produce final binary ADC outputs. The overhead of using value shifted capacitor DAC is the extra latency needed for re-combined logic.