A time-to-digital converter (TDC) that combines the energy efficiency of a successive approximation (SAR) design with the high speed of pipelined converters by leveraging the inherently pipelined nature of time-domain signaling. The TDC achieves high speed by removing a comparator decision from a signal path, instead using AND/OR gates to separate early and late edges. The TDC uses a pipelined SAR architecture to digitize a differential delay between two incoming clock edges with high speed and low power consumption. Described is a modular digital reference voltage generator that can be used for a capacitive digital-to-analog converter (DAC). The generator comprises a decoupling capacitor, one or more clocked comparators, and power transistor(s). A simplified digital low dropout (LDO) circuitry is used to provide fast reference voltage generation with minimal overhead. The LDO circuitry is arrayed using time-interleaved synchronous clocks or staggered asynchronous clocks to provide finer timing resolution.

A time-to-digital converter (TDC) that combines the energy efficiency of a successive approximation (SAR) design with the high speed of pipelined converters by leveraging the inherently pipelined nature of time-domain signaling. The TDC achieves high speed by removing a comparator decision from a signal path, instead using AND/OR gates to separate early and late edges. The TDC uses a pipelined SAR architecture to digitize a differential delay between two incoming clock edges with high speed and low power consumption. Described is a modular digital reference voltage generator that can be used for a capacitive digital-to-analog converter (DAC). The generator comprises a decoupling capacitor, one or more clocked comparators, and power transistor(s). A simplified digital low dropout (LDO) circuitry is used to provide fast reference voltage generation with minimal overhead. The LDO circuitry is arrayed using time-interleaved synchronous clocks or staggered asynchronous clocks to provide finer timing resolution.

An ADC device includes a DAC circuit, a comparator circuit, a SAR decision circuit, an oscillator circuit having a delay unit, and a processing circuit. The oscillator circuit is used for generating the clock signal according to a reset signal and a delay of the delay unit. The processing circuit is used for sequentially generating multiple bit conversion signals associated with multiple different bits of the decision signal, for generating at least one guard signal which follows the multiple bit conversion signals, and then for comparing the at least one guard signal with the reset signal to adjust the delay generated by the delay unit of the oscillator circuit.

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.

A receiver having analog-to-digital converters (ADC) is disclosed. The ADCs may be reconfigured based on the insertion loss mode of the receiver. For example, different portions of a plurality of time-interleaved successive approximation (SAR) ADC slices included in at least one sub-ADC of each time-interleaved ADC may be enabled depending on which of a plurality of insertion loss modes is selected for operation of the receiver.

A receiver having analog-to-digital converters (ADC) is disclosed. The ADCs may be reconfigured based on the insertion loss mode of the receiver. For example, different portions of a plurality of time-interleaved successive approximation (SAR) ADC slices included in at least one sub-ADC of each time-interleaved ADC may be enabled depending on which of a plurality of insertion loss modes is selected for operation of the receiver.

A successive approximation register (SAR) analog-to-digital converter (ADC) includes a comparator, a threshold generator and a controller. The comparator receives an analog signal and the SAR ADC outputs an output codeword. The comparator performs a plurality of first comparisons and a plurality of second comparisons. The controller determines a plurality of most significant bits of the output codeword according to a plurality of first comparison results corresponding to the first comparisons. The first comparisons are performed by comparing the analog signal with a plurality of first thresholds. The controller determines a plurality of least significant bits of the output codeword according to a plurality of second comparison results corresponding to the second comparisons. The second comparisons are performed by comparing the analog signal with a second threshold. The controller controls the threshold generator to produce the plurality of first thresholds and the second threshold according to the first comparison results.

A successive approximation register (SAR) analog-to-digital converter (ADC) includes a comparator, a threshold generator and a controller. The comparator receives an analog signal and the SAR ADC outputs an output codeword. The comparator performs a plurality of first comparisons and a plurality of second comparisons. The controller determines a plurality of most significant bits of the output codeword according to a plurality of first comparison results corresponding to the first comparisons. The first comparisons are performed by comparing the analog signal with a plurality of first thresholds. The controller determines a plurality of least significant bits of the output codeword according to a plurality of second comparison results corresponding to the second comparisons. The second comparisons are performed by comparing the analog signal with a second threshold. The controller controls the threshold generator to produce the plurality of first thresholds and the second threshold according to the first comparison results.

A comparator circuit includes a zeroth capacitor having a first terminal fed with an input voltage, a zeroth inverter having an input terminal connected to a second terminal of the zeroth capacitor at a zeroth node, a first capacitor having a first terminal connected to the output terminal of the zeroth inverter at a first node, a first inverter having an input terminal connected to a second terminal of the first capacitor at a second node, a second inverter having an input terminal connected to the output terminal of the first inverter at a third node, a zeroth switch switching conduction between the zeroth and first nodes, a first switch switching conduction between the second and third nodes, a second switch switching conduction between the first and third nodes, and a third switch switching conduction between the third node and the output terminal of the second inverter.

A comparator circuit includes a zeroth capacitor having a first terminal fed with an input voltage, a zeroth inverter having an input terminal connected to a second terminal of the zeroth capacitor at a zeroth node, a first capacitor having a first terminal connected to the output terminal of the zeroth inverter at a first node, a first inverter having an input terminal connected to a second terminal of the first capacitor at a second node, a second inverter having an input terminal connected to the output terminal of the first inverter at a third node, a zeroth switch switching conduction between the zeroth and first nodes, a first switch switching conduction between the second and third nodes, a second switch switching conduction between the first and third nodes, and a third switch switching conduction between the third node and the output terminal of the second inverter.