Abstract: An analog-to-digital converter is disclosed comprising a resonant oscillator comprising an input operable to receive an analog input signal and an output operable to output an oscillating signal. A DC offset detector detects a DC offset in the oscillating signal caused by the analog input signal, wherein the DC offset is converted into a digital output signal representing the analog input signal.

Abstract: The present invention provides an analog-to-digital converter, which comprises an integration circuit, a threshold signal generating circuit, a main comparison circuit, a sub comparison circuit, a counter, and a decoder. The integration circuit integrates an input signal and produces an integration signal. The threshold signal generating circuit generates a main threshold signal and a plurality of sub threshold signals. The main comparison circuit produces a plurality of main comparison signals according the integration signal and the main threshold signal. The sub comparison circuit produces a plurality of sub comparison signals according to the integration signal and the plurality of sub threshold signals. The counter counts the plurality of main comparison signals and produces a first counting signal. The decoder decodes the plurality of sub comparison signals and produces a second count signal. The first count signal and the second count signal are used for producing a digital signal.

Abstract: A time difference adjustment circuit includes two flip-flop circuits, a delay circuit, and a reset circuit. The delay circuit includes first and second transistors of a first polarity and third and fourth transistors of a second polarity, wherein drains of the first and third transistors are coupled to each other, drains of the second and fourth transistors are coupled to each other, the drains of the first and third transistors and a gate of the fourth transistor are coupled to each other, an input signal is coupled to a gate of the first transistor, an output signal is supplied from the drains of the second and fourth transistors, and first and second reset signals are respectively coupled to gates of the second and third transistors.

Abstract: Disclosed is an analog-digital converter which includes a pre-amplifier configured to output a comparison result between a sampled analog input signal and a reference signal and to control a power supply operation in response to a power control signal; a digital signal processor configured to generate a digital signal based on the comparison result; a power controller configured to generate an amplifier operation clock signal for controlling the pre-amplifier; and a counter configured to count the number of falling edges of the amplifier operation clock signal and to detect a power interruption point of time of the pre-amplifier according to the counted falling edge number. The power controller generates the power control signal for interrupting a power to be supplied to the pre-amplifier when the power interruption point of time of the pre-amplifier is detected.

Abstract: Described is an apparatus comprising: a first phase frequency detector (PFD) to determine a coarse phase difference between a first clock signal and a second clock signal, the first PFD to generate a first output indicating the coarse phase difference; and a second PFD, coupled to the first PFD, to determine a fine phase difference between the first clock signal and the second clock signal, the second PFD to generate a second output indicating the fine phase difference.

Abstract: A method is provided. An analog signal is received. The analog input signal is compared to first and second reference signals to generate a first comparison result, and the first comparison result and a first time stamp corresponding to the first comparison result are registered. A first portion of a digital signal is generated from the first comparison result. If the comparison result remains substantially the same for a predetermined interval, an ADC is enabled to generate a second comparison result at a sampling instant. A second time stamp that corresponds to the sampling instant is generated. The second comparison result and a second time stamp corresponding to the first comparison result are registered, and a second portion of the digital signal is generated from the second comparison result.

Abstract: A time-to-digital converting circuit includes a first flip-flop and a second flip-flop. The time-to-digital converting circuit a first delay controlling circuit that outputs a first data signal obtained by controlling a delay time of the reference data signal input thereto via the first signal input terminal based on the first output signal and a first clock signal obtained by controlling a delay time of the reference clock signal input thereto via the second signal input terminal based on the first output signal.

Abstract: Time-to-digital converters adapted to analog and digital inputs and methods of use are described. A time-to-digital converter has an event frame latches and logic module with memory cells, an analog front-end module connected to the memory cells, and a bin increment generator module connected to the memory cells. The bin increment generator is configured to issue bin increments separated by a time increment, and the analog front end is configured to issue a start event followed by a plurality of stop events. Upon receipt of a first time increment following a start event, the event frame latches and logic module updates a first memory cell with a first bit-type; upon receipt of a second time increment following an intervening stop event, the event frame latches and logic module updates a second memory cell with a second bit-type different from the first bit-type.

Abstract: An endoscope system may include: an insertion section that is inserted into an object under examination, having an image capturing unit that successively outputs a pixel signal of a strength responsive to the amount of light of the pixel, and a time converter that converts the intensity of the pixel signal to time information representing a time interval by a time width and that transmits the converted time information; a transfer section that guides the outside of the object under examination the time information transmitted from the time converter; and an external apparatus positioned outside the object under examination, having a time interval converter that receives the time information guided by the transfer section and converts to a digital signal and outputs the intensity of the pixel signal represented by the received time information and an image processing unit that outputs an image responsive to the pixel signal.

Abstract: The charge-to-digital timer apparatus and method disclosed herein estimates the elapsed time between two signals, e.g., a start signal and a stop signal. To that end, at least a capacitive load is charged with a known current to generate a load voltage. Subsequently, a first voltage is ramped in a plurality of discrete voltage steps associated with a plurality of known capacitances until the ramped voltage satisfies a predetermined criterion relative to a second voltage. The elapsed time is determined from the discrete voltage steps, one of the first and second voltages, the known current, and the known capacitive load.

Abstract: Processing a signal by receiving an analog input signal located outside of a first Nyquist zone that is between 0 and fs/2; passing the analog input signal through an M-channel time-interleaved analog-to-digital converter (TI-ADC) to generate a TI-ADC output signal; and estimating and correcting a timing skew error in the TI-ADC output signal. Alternatively, an electronic circuit that includes an input for an analog input signal, an M-channel time-interleaved analog-to-digital converter (TI-ADC) and a timing skew error estimating and correcting circuitry. The analog input signal is located outside of a first Nyquist zone that is between 0 and fs/2. The TI-ADC receives the analog input signal and generates a TI-ADC output signal. The timing skew error estimating and correcting circuitry estimates and corrects a timing skew error in the TI-ADC output signal.

Abstract: An analog-to-digital converter (ADC) comprises a plurality of time-interleaved integrating ADCs having feedback from an integrated output signal. In variations, the time-interleaved integrating ADCs have feedback compensation from at least one measure of quantization error. The time-interleaved integrating ADCs may also share a single comparator and may also share a single current source.

Abstract: A system for processing signals may be configured to apply digital conversion to analog signals, and to apply, prior to the analog-to-digital conversion, a gain to at least a portion of the analog signals. The gain may be controlled and/or adjusted based on processing of digital output generated based on the analog-to-digital conversion. The system may comprise a plurality of sampling slices, which may be configured to provide the analog-to-digital conversion in interleaved (e.g., time-interleaved) manner. Each of the sampling slices may comprise a dedicated gain element, for applying gain to signals handled by the corresponding slice. The gain applied by the gain elements of the sampling slices may be controlled, independently, collectively, and/or in based on grouping into subsets. The gain may be controlled based on application of a particular gain control algorithm, which may be selected from a plurality of predefined algorithms.

Abstract: According to one general aspect, a distributed threshold adjuster (DTA) may be interspersed between stages of a multistage amplifier to adjust the DC voltage of an input signal. The DTA may include an input signal terminal configured to receive the input signal. The DTA may also include a plurality of current sources configured to produce an adjustment current signal whose amperage is configured to be increased or decreased by fixed steps in order to adjust the DC voltage of the input signal. The DTA may include a control unit configured to selectively turn on or off the individual current sources of the plurality of current sources to select the amperage of the adjustment current signal. The DTA may further include an output terminal configured to produce an output signal, comprising a combination of the input signal and the adjustment current signal, to a stage of a multistage amplifier.

Abstract: There are provided an analog-to-digital signal conversion method and apparatus therefor, and a digital phase locked loop circuit including the same. The analog-to-digital signal conversion method may include: generating a first digital output signal having N number of bits by comparing each of N number of delay signals detected from output terminals of N number of delay cells with a reference signal; generating a second digital output signal by comparing an auxiliary delay signal generated by an (N+1)th delay cell with the reference signal; and determining a change in a delay time of each of the N number of delay cells based on the first digital output signal and the second digital output signal.

Abstract: A timing circuit that includes a first serializer/deserializer (SERDES) configured to receive a parallel rate clock signal and a system clock start signal from an imaging system and generate a first output, a second SERDES configured to receive a stop signal that is based on an output from the medical imaging system and generate a second output, and a timestamp calculator configured to utilize the first and second outputs to generate a timestamp. A medical imaging system and a method of operating a timing circuit are also described.

Abstract: A time-to-digital conversion circuit for converting a time difference between two input signals to a 1-bit digital value, and adjusting the time difference between the two input signals to generate two output signals includes: a phase comparator configured to compare phases of the two input signals with each other to generate the digital value; a phase selector configured to output one of the two input signals which has a leading phase as a first signal, and the other of the two input signals which has a lagging phase as a second signal; and a delay unit configured to output the first signal with a delay, wherein the time-to-digital conversion circuit outputs the signal output from the delay unit and the second signal as the two output signals.

Abstract: A TD converter is provided for digitally converting a delay time value into a digital value. In the TD converter, an oscillator circuit part inputs time domain data. A first-state counter circuit part measures a number of waves of an output oscillation waveform from the oscillator circuit part when time domain data is in a first state, and a second-state counter circuit part measures a number of waves of the output oscillation waveform from the oscillator circuit part when the time domain data is in a second state. An output signal generator part generates an output signal based on output count values of the first-state counter circuit part and the second-state counter circuit part, and a frequency control circuit controls the oscillator circuit part to always oscillate and to control an oscillation frequency of the oscillator circuit part.

Abstract: A comparison circuit is provided and includes first and second comparators and a first time-to-digital comparator. The first comparator with a first offset voltage receives an input signal and generates a first comparison signal and a first inverse comparison signal. The second comparator receives the input signal and generates a second comparison signal and a second inverse comparison signal. The first offset voltage is larger than the second offset voltage. The first time-to-digital comparator receives the first comparison signal and the second inverse comparison signal and generates first and second determination signals according to the first comparison signal and the second inverse comparison signal. The first and second determination signals indicate whether a voltage of the input signal is larger than a first middle voltage. The first middle voltage is equal to a half of the sum of the first offset voltage and the second offset voltage.

Abstract: Disclosed is a time-to-digital (TDC) converter comprising an analog voltage source. An analog-to-digital converter quantizes two voltage samples in response to receiving a first input signal at a first time t1 and a second input signal at a second time t2. The first and second digital signals are combined to produce a digital signal that represents the difference (t2?t1).

Abstract: Phase noise in a first clock signal is measured using a time to digital converter (TDC) by determining variations in the phase delay between the first clock signal and a second clock signal. The TDC can include first and second series interconnections of delay elements, first and second sets of latches, and processing circuitry coupled to the latches and configured to determine the phase delay. The TDC can include a series interconnection of delay elements, latches, and circuitry configured to selectively adjust the control signal connected to the delay elements based on the output of the latches. The phase noise measurement can be used in a sampling circuit, so as to produce a second data signal from a first data signal based on the first clock signal and the measured phase noise.

Abstract: The solution according to the invention consisting in conversion of a time interval to a digital word of a number of bits equal to n by the use of the array (A) of binary-scaled capacitors (C.n-1, . . . , C0) is characterized in that the time interval whose both start and end are detected by the control module (CM) is first mapped to a portion of electric charge delivered by the current source (I) and successively accumulated in the capacitors ((Cn-1, . . . , C0)) in the order of decreasing capacitances starting from the capacitor (Cn-1) having the highest capacitance value in the array, and when the control module (CM) detects the end of the time interval, the charge accumulated in the capacitor (Cx) charged recently is successively transferred by the use of the current source (I) to the capacitors of lower capacitance values.

Abstract: An AD converter includes a VT converter circuit part which inputs an analog input voltage and a sampling clock, converts the analog input voltage to a corresponding delay time, and outputs time domain data. A ring oscillator circuit part of N stages inputs the time domain data, and an error propagation circuit part takes out delay information containing a quantization error from phase information of the ring oscillator circuit part of the previous stage, and propagate the delay information to the ring oscillator circuit part of a subsequent stage. A counter circuit part measures a number of waves of an output oscillation waveform of the ring oscillator circuit part of each stage, and an output signal generator part generates an output signal from an output counted value of each counter circuit part. A reset part resets each error propagation circuit part and each counter circuit part with a sampling clock.

Abstract: Disclosed is a low-power and high-resolution time-to-digital converter including: a coarse delay cell configured to delay a reference clock by a coarse delay time and output the reference clock; a rising-edge retimer configured to output a rising-edge retimed clock synchronized with the rising-edge of a DCO clock in response to the reference clock; a falling-edge retimer configured to output a falling-edge retimed clock synchronized with the falling-edge of the DCO clock; a firs sampler configured to latches output of the coarse delay cell in response to the rising-edge retimed clock and the falling-edge retimed clock; and a pseudo-thermometer code edge detector configured to detect a rising-edge fractional phase error between the reference clock and the rising-edge retimed clock as a coarse phase error from a signal output by the first sampler, and detect a falling-edge fractional phase error between the reference clock and the falling-edge retimed clock.

Abstract: In accordance with embodiments of the present disclosure, a continuous-time incremental analog-to-digital converter (ADC) may include a plurality of resettable integrators and a feed-in gain element. Each integrator may be configured to convert a sum of signals received at its input to a signal indicative of an integral over time of the sum of signals. The plurality of integrators may include a first-stage integrator configured to receive at its input the baseband signal and a final-stage integrator configured to produce at its output a final-stage analog signal. The plurality of integrators may be arranged in a cascade configuration such that an output of each of the plurality of integrators other than the final-stage integrator is coupled to the input of a subsequent integrator. The feed-in gain element may be coupled between the input of the first-stage integrator and the input of another integrator of the plurality of integrators.

Abstract: Provided is a time-domain voltage comparator including a voltage-time converter. The voltage-time converter includes a conversion unit and an output unit. The conversion unit includes a first MOS transistor which shifts a voltage level of the first detection node according to an external first voltage signal, and a second MOS transistor which shifts a voltage level of the second detection node according to an external second voltage signal. The output unit generates first and second output signals in response to voltages of the first and second detection nodes. The output unit determines a shifted time of the first output signal according to a voltage level of the first detection node and determines a shifted time of the second output signal according to a voltage level of the second detection node.

Abstract: Provided are a distance measuring device using an impulse signal and a receiving device thereof. The distance measuring device includes: a transmitting device transmitting an impulse signal; and a receiving device receiving the impulse signal and measuring a time interval (hereinafter, referred to as a delay time) between a transmitting timing and a receiving timing of the impulse signal, wherein the receiving device measures the delay time through a Time to Digital Converter (TDC) technique. According to the present invention, the distance measuring device measures the distance accurately and speedly.

Abstract: Provided is an analog-to-digital (A/D) converter that may be used in an image sensor and a ramp signal generator that is used in an A/D converter. The ramp signal generator may generate a ramp signal and a reference voltage signal that include noise that has same noise characteristics that are input into the ramp signal, such that the signal to noise ratio (SNR) is improved and the image quality is also improved.

Abstract: There is a need to provide an AD converter capable of reducing occurrence of a noise. An AD converter includes an operational amplifier and a clip circuit. The operational amplifier receives ramp voltage and voltage for an analog signal and allows output terminal voltage to transition from an H level to an L level when a change in the ramp voltage reaches the voltage for the analog signal. The clip circuit fixes an output terminal of the operational amplifier to clipping voltage after output voltage for the operational amplifier reaches threshold voltage for a latch circuit. Therefore, the AD converter can limit a range of output voltage, as a source of noise, for the operational amplifier and eliminate an unnecessary change in the output voltage after the threshold voltage for the latch circuit is reached.

Abstract: An A/D conversion apparatus includes an N-stage pulse circulating circuit including N (N is a natural number, N?3) inverting circuits connected in a ring shape, the inverting circuits delaying an input pulse signal by a delay time corresponding to an amplitude of a separately input analog input signal, and outputting inverted pulse signals obtained by inverting the pulse signal, a counter unit that counts a number of circulations by which the pulse signal has circulated in the pulse circulating circuit within a predetermined time based on the inverted pulse signal output from one of the N inverting circuits, and a switching unit that switches an output destination of the inverted pulse signal, which is output from an inverting circuit of an Mth (M is an odd natural number, 1?M?N?1) stage of the pulse circulating circuit, according to a change in an operation environment.

Abstract: A time measurement circuit measures the time difference between edges of a first signal and a second signal. A sampling circuit acquires the logical level of the first signal at a timing of the edge of the second signal. When a sampling circuit enters a metastable state, an output signal thereof transits with a long time scale. A transition time measurement circuit measures a transition time (settling time) of the output signal of the sampling circuit in the metastable state.

Abstract: An A/D converter having high accuracy and high throughput irrespective of characteristic variations of analog circuits is provided. The A/D converter includes a voltage-to-time converter configured to synchronize with a sampling clock signal and convert an input analog voltage to a time difference between two signals, and a plurality of time-to-digital converters each configured to convert the time difference between the two signals to a digital value. The plurality of time-to-digital converters operate in an interleaved manner.

Abstract: An apparatus for measuring time interval between two edges of a clock signal and includes an edge generator, a first multi-tap delay module, a second multi-tap delay module, and a multi-element phase detector. The edge generator produces a first edge at a first output node and a second selected edge at a second output node. First multi-tap delay module provides a first incremental delay at each tap to the first edge. Second multi-tap delay module provides a second incremental delay at each tap to the second selected edge. Each element of the multi-element phase detector has first and second input terminals. The first input terminal is coupled to a selected tap of the first multi-tap delay module and the second input terminal is coupled to a corresponding tap of the second multi-tap delay module. The output terminals of the multi-element phase detector provide the value of the time interval.

Abstract: A method for converting an analog signal to a digital signal is provided. Initially, a digital representation of a portion of an analog signal is generated. Residue of the analog signal is then sampled at a sampling instant so as to generate a residue sample. A signal having a frequency that is proportional to the voltage of the residue sample is generated, and the signal is measured to generate coarse and fine measurements of the frequency. A digital representation of the residue sample from the coarse and fine measurements is then generated.

Abstract: A method for converting an analog signal to a digital signal is provided. Initially, a digital representation of a portion of an analog signal is generated. Residue of the analog signal is then sampled at a sampling instant so as to generate a residue sample. A signal having a frequency that is proportional to the voltage of the residue sample is generated, and the signal is measured to generate coarse and fine measurements of the frequency. A digital representation of the residue sample from the coarse and fine measurements is then generated.

Abstract: An A/D conversion circuit includes: a pulse transit circuit into which either a power supply or current source and also a pulse signal is input, and through which the pulse signal transits; a transit position detection section that detects a transit position of the pulse signal within the pulse transit circuit, and outputs data in accordance with the transit position; and a digital data creation section that, based on the data output by the transit position detection section, creates digital data that corresponds to the size of the power supply or current source. The pulse transit circuit is formed by a plurality of inverter circuits that are joined together in series, and the plurality of inverter circuits are formed by identical logical elements in which delay times between input signals and output signals change in accordance with the size of the power supply or current source.

Abstract: An A/D conversion circuit includes a pulse transit circuit, first and second pulse transit position detection circuits, and a digital signal generation circuit. The first pulse transit position detection circuit detects a transit position of the pulse signal output from the pulse transit circuit and generates a logical signal according to the transit position. The second pulse transit position detection circuit detects the circling number of the pulse signal output from the pulse transit circuit and generates a logical signal according to the circling number. The digital signal generation circuit synthesizes the logical signals output from the first and second pulse transit position detection circuits and generates a digital signal according to a size of an analog signal VA.

Abstract: Processing a signal by receiving an analog input signal located outside of a first Nyquist zone that is between 0 and fs/2; passing the analog input signal through an M-channel time-interleaved analog-to-digital converter (TI-ADC) to generate a TI-ADC output signal; and estimating and correcting a timing skew error in the TI-ADC output signal. Alternatively, an electronic circuit that includes an input for an analog input signal, an M-channel time-interleaved analog-to-digital converter (TI-ADC) and a timing skew error estimating and correcting circuitry. The analog input signal is located outside of a first Nyquist zone that is between 0 and fs/2. The TI-ADC receives the analog input signal and generates a TI-ADC output signal. The timing skew error estimating and correcting circuitry estimates and corrects a timing skew error in the TI-ADC output signal.

Abstract: The influence of a jitter of a sampling clock of an analog-to-digital converter is digitally corrected at low power consumption. The sampling clock of the analog-to-digital converter is generated by a phase locked loop (PLL) using a reference clock, which has a lower frequency and lower jitter than the sampling clock, as a source oscillation. A time-to-digital converter (TDC) converts a timing error at a timing where the sampling clock and the reference clock are synchronized with each other into a digital value. Incidentally, a timing error at a sampling timing where the reference clock is not present is generated by interpolating a detected timing error. Thus, a jitter value of the sampling clock at each sampling timing is obtained. A sampling voltage error is calculated from the jitter value and the output of the analog-to-digital converter is digitally corrected.

Abstract: According to one embodiment, a digital filter circuit includes an EXOR circuit, a clock gating circuit, a reset control circuit, a counter, a filter time setting circuit, a comparator, and a decoder. The clock gating circuit outputs a clock gating signal. The reset control circuit generates a first signal. The counter generates a count signal. The filter time setting circuit latches the count signal when the first signal is in the enable state, and outputs a latched count value as a second signal. The comparator receives the count signal and the second signal, and outputs a third signal of the enable state when the value of the count signal and the value of the second signal match each other.

Abstract: A time-domain voltage comparator for an analog-to-digital converter includes a first voltage-to-time converter configured to be connected in series with at least one time delay cell and convert an input voltage into time information; a second voltage-to-time converter configured to be connected in series with at least one time delay cell and convert an input voltage into time information; and a phase comparator configured to determine a difference between times outputted from the first voltage-to-time converter and the second voltage-to-time converter.

Abstract: A non-binary successive approximation analogue to digital converter, for converting using successive conversion steps, is operable in first and second modes. The first and second modes have different noise properties and the converter is switched between the modes during the conversion process.

Abstract: Provided are a TDC having a pipeline or cyclic structure and an operating method thereof. The TDC includes a first stage block and a second stage block. The first stage block detects a first bit of a digital code for a time difference between first and second input signals. The second stage block detects a second bit of the digital code for a time difference between first and second output signals of the first stage block. The first stage block amplifies a time difference between first and second delay signals for the first and second input signals to generate the first and second output signals, and transfers the first and second output signals to the second stage block.

Abstract: A tracking analog-to-digital converter “ADC” with a self-controlled variable clock comprises: a digital register; a digital-to-analog converter “DAC” coupled to said digital register providing an analog feedback signal; a comparator coupled to an analog input signal and said analog feedback signal and providing a comparison signal based on a comparison between said analog input signal and said analog feedback signal, said comparison signal being coupled to the digital register; a means for determining comparator readiness to determine if said comparator is ready, indicating that said comparison signal can be reliably read, said means for determining comparator readiness further comprising a determination of a comparison ready indicator; a means for clocking to generate a clock signal to drive said digital register in response to said means for determining comparator readiness determining that said comparator is ready; and said digital register being configured to count in response to said clock signal based o

Abstract: A system and method are provided for adaptively controlling timing in SAR ADC of a sampled analog signal within a conversion period. A state machine maintains a set of SAR states including a sampling state and a plurality of bit conversion states. A reference generator generates a quantization level reference for each of the bit conversion states within a parametric settling time thereof. A comparator compares the sampled analog signal with the quantization level reference over a parametric propagation time for determining a hit value for each hit conversion state. A clock generator adaptively defines signals for clocking the state machine and comparator for each SAR state, thereby adaptively delaying bit determination in each bit conversion state by an integration period not less than the settling time, while adaptively delaying quantization level reference generation for a next bit conversion state by a regeneration period not less than the propagation time.

Abstract: In a time-to-digital conversion stage, a time-to-digital conversion circuit outputs an n-bit digital signal, which represents an integer value ranging from ?(2n-1?1) to +(2n-1?1), based on a phase difference between a first and a second signals input thereto; a time difference amplifier circuit amplifies the phase difference between the first and the second signals 2n-1 times, and outputs two signals having an amplified phase difference therebetween; a delay adjustment circuit adds a phase difference dependent on the digital signal to the two signals output from the time difference amplifier circuit, and outputs another two signals; an output detection circuit detects that the delay adjustment circuit has output the another two signals, and outputs a detection signal; and a storage circuit latches the digital signal in synchronism with the detection signal. Multi-stage coupling of the time-to-digital conversion stages forms a pipeline time-to-digital converter.

Abstract: A Time-to-Digital Converter (TDC) is provided.

Abstract: A Time-to-Digital Converter (TDC) is constructed using simple digital delay circuits. The design uses a clock compensation scheme to modify and adjust the TDC's operation under integrated circuit fabrication process variations. The TDC design is based on a novel digital processing algorithm that produces one conversion every clock cycle. Therefore, this TDC is the “first” single cycle latency TDC targeted at high speed circuit applications such as (but not limited to) time-based Analog to Digital Converters (ADCs) for direct analog to digital conversion of radio frequency signals in wireless communication systems and high speed signal measurement applications. Due to its hierarchical design approach, the TDC design uses an optimized number of delay circuits and therefore requires very little power consumption and silicon area.

Abstract: A circuit and method for providing a digital output indicative of the time at which an event occurred is disclosed. In one aspect, the circuit includes a fine timing circuit configured to determine in which sub-interval of a clock period the event occurred, and a correction circuit configured to correct an erroneous offset between a first and second clock signals in the fine timing circuit. The correction circuit includes a synch circuit configured to determine in which half of the clock period the event occurred so as to correct for erroneous offset in the fine timing circuit.

Abstract: An AD converter includes a VT converter circuit part which inputs an analog input voltage and a sampling clock, converts the analog input voltage to a corresponding delay time, and outputs time domain data. A ring oscillator circuit part of N stages inputs the time domain data, and an error propagation circuit part takes out delay information containing a quantization error from phase information of the ring oscillator circuit part of the previous stage, and propagate the delay information to the ring oscillator circuit part of a subsequent stage. A counter circuit part measures a number of waves of an output oscillation waveform of the ring oscillator circuit part of each stage, and an output signal generator part generates an output signal from an output counted value of each counter circuit part. A reset part resets each error propagation circuit part and each counter circuit part with a sampling clock.