A multi-layer time-interleaving (TI) device and method of operation therefor. This device includes a plurality of TI layers configured to receive a plurality of input clock signals and to output a plurality of output clock signals, each of which can be configured to drive subsequent devices. The layers include at least a first and second layer including a fine-grain propagation device and a barrel-shifting propagation device configured to retime the plurality of input clock signals to produce divided output clock signals. The device can include additional barrel-shifting propagation devices to time interleave an initial two layers to produce one or more additional layers. Using negative phase stepping, the plurality of output clock signals is produced with optimal timing margin and synchronized on a single clock edge.

An analog-to-digital converter for an image sensor comprises a counter circuit to generate a respective counter bit in response to a counter state of the counter circuit, and a storage circuit for storing a respective storage state in response the respective counter bit. The converter further comprises a comparator circuit for generating a level of a comparison signal, and a synchronization circuit to generate a write control signal for controlling the storing of the respective storage state in the respective storage cell. The counter circuit is configured to change the counter state, when a first edge of a cycle of the clock signal is applied to the counter circuit, and to generate the write control signal, when a second edge of the cycle of the clock signal being subsequent to the first edge of the cycle of the clock signal is applied to the synchronization circuit.

The present disclosure provides a circuit for generating a multi-phase clock having random disturbance added thereto. The circuit for generating a clock includes a main clock module, a random signal generation module and a buffer matrix switch module. The main clock module generates N multi-phase clock signals; and the buffer matrix switch module randomly switches, under the control of a random control signal output by the random signal generation module, transmission paths of the input N multi-phase clock signals, and outputs N multi-phase clock signals with random disturbance. In the present disclosure, the clock phase error is whitened by adding random disturbance. Only with a small loss of signal-to-noise ratio, the influence of a multi-phase clock phase error on the performance of a high-precision TI ADC can be eliminated in real time, and the influence of the fluctuation of a clock phase error can be tracked and eliminated.

A track and hold circuit includes a signal input terminal, a clock input terminal, an output terminal, a transistor, and a bootstrapping circuit with a transformer. The transistor includes a source, a drain, and a gate, where the source is coupled to the signal input terminal, and the drain is coupled to the output terminal. The transformer includes a primary winding coupled to the clock input terminal, and a secondary winding. The secondary winding is coupled between the source and the gate to control a gate-source voltage of the transistor.

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.

An interleaved analog-to-digital conversion (ADC) system may have timing errors in a time domain that is corrected using phase compensation in a phase domain. The ADC system may include sub-ADCs, each receiving a clock signal, which is associated with a representation of a timing skew value, reflecting an undesired timing error. A mixer may have sub-mixers, each receiving a sub-ADC output signal and a compensated numerically controlled oscillator (NCO) value. A combiner may combine the sub-mixer output signals. A decimator may decimate the output of the combiner. Each timing skew value is in a time domain. A compensated NCO value is determined using a respective phase skew value. Each phase skew value is an offset value in phase and is not a value in time. Each phase skew value in a phase domain compensates the respective timing skew value in a time domain. Multiple ADC systems and methods are described.

An ADC sampling data identification method and system, integrated circuit and decoding device are disclosed. The ADC sampling data identification method includes in the integrated circuit, converting sampling data from n time interleaved ADC chips into serial data, generating a preamble sequence, combining the serial data with the generated preamble sequence to obtain new serial data, sending the new serial data to a decoding device, generating a clock signal that matches the new serial data, and sending the clock signal to the decoding device; and in the decoding device, receiving the new serial data and the clock signal from the ADC integrated circuit, obtaining the preamble sequence for combining according to an agreement with the ADC integrated circuit, and identifying a start position of the sampling data from the time interleaved ADC chips.

An analog-to-digital converter for an image sensor comprises a counter circuit to generate a respective counter bit in response to a counter state of the counter circuit, and a storage circuit for storing a respective storage state in response the respective counter bit. The converter further comprises a comparator circuit for generating a level of a comparison signal, and a synchronization circuit to generate a write control signal for controlling the storing of the respective storage state in the respective storage cell. The counter circuit is configured to change the counter state, when a first edge of a cycle of the clock signal is applied to the counter circuit, and to generate the write control signal, when a second edge of the cycle of the clock signal being subsequent to the first edge of the cycle of the clock signal is applied to the synchronization circuit.

Described herein are techniques for mitigating bandwidth mismatch in time-interleaved (TI) analog-to-digital converters (ADC). The techniques described herein involve spreading the energy associated with spurious tones resulting from bandwidth mismatch across the frequency spectrum, thereby reducing the overall impact of each individual tone. In some embodiments, for example, the tones may disappear under the noise floor. Spreading the energy associated with the spurious tones can be achieved by increasing the periodicity of the phase oscillation. This, in turn, can be achieved by introducing, in the phase oscillation, artificial phase shifts in addition to the phase shifts arising due to bandwidth mismatch. In one example, increasing the periodicity of a phase oscillation from 4 phase samples to 8 phase samples can result in a reduction in the power of a tone as high as 7 dB.

In certain aspects, a method for providing a first drive clock signal and a second drive clock signal to a first sub-digital-to-analog converter (sub-DAC) and a second sub-DAC includes receiving an input clock signal, and dividing the input clock signal to generate a first divided clock signal and a second divided clock signal. The method also includes gating the input clock signal using the first divided clock signal to generate the first drive clock signal, and inputting the first drive clock signal to a clock input of the first sub-DAC. The method further includes gating the input clock signal using the second divided clock signal to generate the second drive clock signal, and inputting the second drive clock signal to a clock input of the second sub-DAC.