An analog-to-digital converter includes: a voltage-current converter receiving an analog input voltage, generating a first digital signal from the analog input voltage, and outputting a residual current remaining after the first digital signal; a current-time converter converting the residual current into a current time in a time domain; and a time-digital converter receiving the residual time, and generating a second digital signal from the residual time, wherein the first digital signal and the second digital signal are sequences of digital codes representing respective signal levels of the analog input voltage.

A method of operating a pipelined analog-to-digital converter (ADC) having a plurality of output stages includes: performing a first calibration process for the pipelined ADC to update a parameter vector of the pipelined ADC, where components of the parameter vector are used for correcting nonlinearity of the pipelined ADC, where performing the first calibration process includes: providing an input signal to the pipelined ADC; converting, by the pipelined ADC, the input signal into a first digital output; providing a scaled version of the input signal to the pipelined ADC, where the scaled version of the input signal is generated by scaling the input signal by a scale factor; converting, by the pipelined ADC, the scaled version of the input signal into a second digital output; and calibrating the pipelined ADC using the first digital output and the second digital output.

An analog-to-digital converter (ADC) includes a first ADC stage with a first sub-ADC stage configured to sample the analog input voltage in response to a first phase clock signal and output a first digital value corresponding to an analog input voltage in response to a second phase clock signal. A current mode DAC stage is configured to convert the analog input voltage and the first digital value to respective first and second current signals, determine a residue current signal representing a difference between the first and the second current signal, and convert the residue current signal to an analog residual voltage signal. A second ADC stage is coupled to the first ADC stage to receive the analog residual voltage signal, and convert the analog residue voltage signal to a second digital value. An alignment and digital error correction stage is configured to combine the first and the second digital values.

An ANC system includes an AD converter which performs AD conversion on an external noise signal, an ANC signal generator which generates an ANC signal for canceling a noise component arriving at the ears of a user based on an output signal of the AD converter, and a level detector which detects a level of the output signal and causes the ANC signal generator to power down in response to the level. The level detector measures a time for which the level is equal to or less than a predetermined first threshold value, causes the ANC signal generator or a portion of blocks of the AD converter to power down after the measured time exceeds a predetermined value, and causes the ANC signal generator or a portion of blocks of the AD converter to return from the power down when the level exceeds a predetermined second threshold value.

Techniques are provided for implementing a file system format for persistent memory. A node, with persistent memory, receives an operation associated with a file identifier and file system instance information. A list of file system info objects are evaluated to identify a file system info object matching the file system instance information. An inofile, identified by the file system info object as being associated with inodes of files within an instance of the file system targeted by the operation, is traversed to identify an inode matching the file identifier. If the inode has an indicator that the file is tiered into the persistent memory, then the inode it utilized to facilitate execution of the operation upon the persistent memory. Otherwise, the operation is routed to a storage file system tier for execution by a storage file system upon storage associated with the node.

The exemplified disclosure presents a successive approximation register analog-to-digital converter circuit that comprises a two-step (e.g., two-stage) analog-to-digital converter (ADC) that operates a 1st-stage successive approximation register (SAR) in the continuous time (CT) domain (also referred to as a “1-st stage CTSAR”) that then feeds a sampling operation location in the second stage. Without a front-end sampling circuit in the 1st-stage, the exemplary successive approximation analog-to-digital converter circuit can avoid high sampling noise associated with such sampling operation and thus can be configured with a substantially smaller input capacitor size (e.g., at least 20 times smaller) as compared to conventional Nyquist ADC with a front-end sample-and-hold circuit.

An analog-to-digital converter (ADC) includes a coarse ADC that receives an analog input voltage, generates a first digital signal based on the analog input voltage using a successive approximation register (SAR) method, and outputs a residual voltage remaining after the first digital signal is generated. The ADC further includes an amplifier that receives the residual voltage and a test voltage, generates a residual current by amplifying the residual voltage by a predetermined gain, and generates a test current by amplifying the test voltage by the gain. The ADC further includes a fine ADC that receives the residual current and generates a second digital signal based on the residual current using the SAR method, and an auxiliary path that receives the test current and generates a gain correction signal based on the test current. The gain of the amplifier is adjusted based on the gain correction signal.

A two-stage successive-approximation-register (SAR) analog-to-digital converter (ADC) comprising is described. The SAR ADC includes a first stage comprising a SAR ADC; a voltage-to-time interface that translates a voltage-domain residue from the SAR ADC to a time-domain residue; and a second stage comprising a time-to-digital converter (TDC) that resolves multiple bits from the time-domain residue.

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 differential amplifier includes a positive leg, a negative leg, and biasing circuitry. The positive leg includes at least one positive leg transistor, a first positive leg degeneration capacitor, and positive leg degeneration capacitor biasing circuitry configured to bias the first degeneration capacitor during a reset period. The negative leg includes at least one negative leg transistor, a negative leg degeneration capacitor, and negative leg degeneration capacitor biasing circuitry configured to bias the negative leg degeneration capacitor during the reset period. The biasing circuitry biases current of both the at least one positive leg transistor and the at least one negative leg transistor based on capacitance of the first positive leg degeneration capacitor, capacitance of the first negative leg degeneration capacitor, and a sampling time during an amplification period. The differential amplifier may be a stage amplifier in an Analog to Digital Converter (ADC).