An apparatus is disclosed for pipelined analog-to-digital conversion. In an example aspect, the apparatus includes a pipelined analog-to-digital converter (ADC). The pipelined ADC includes a first stage and a second stage. The first stage includes a sampler and a quantizer coupled to the sampler. The first stage also includes a current distribution circuit coupled to the sampler. The second stage includes a sampler coupled to the current distribution circuit and a quantizer coupled to the sampler of the second stage.

A pipeline analog to digital converter includes a “k” number of stages and an output data register. A first stage of the “k” number of stages is configured to receive an analog differential input signal and produce a first digital output and a first single ended analog output. A second stage of the “k” number of stages is configured to receive the first single ended analog output and produce a second digital output. The output data register is configured to generate an output digital value based on the first and second digital outputs.

A pipeline analog to digital converter includes a “k” number of stages and an output data register. A first stage of the “k” number of stages is configured to receive an analog differential input signal and produce a first digital output and a first single ended analog output. A second stage of the “k” number of stages is configured to receive the first single ended analog output and produce a second digital output. The output data register is configured to generate an output digital value based on the first and second digital outputs.

A biasing scheme for a voltage-to-time converter (VTC). An example biasing circuit generally includes a reference current source; a feedback loop current source; an amplifier having a first input coupled to a target voltage node, having a second input, and having an output coupled to a control input of the reference current source and to a control input of the feedback loop current source; a first capacitive element; a first switch coupled in parallel with the first capacitive element; a second switch coupled between the feedback loop current source and the first capacitive element; and a third switch coupled between the first capacitive element and the second input of the amplifier.

An analog-to-digital converter, ADC, circuitry, comprises: an integrator connected to a capacitor, the integrator being configured to switch between integrating an analog input signal for ramping an integrator output and integrating a reference input signal for returning integrator output towards a threshold; a comparator for comparing integrator output to the threshold; and a timer for determining a time duration during which the reference input signal is integrated, the time duration providing a digital representation of an analog input signal value; the ADC circuitry further comprising a feedforward noise shaping loop configured to store a quantization error signal based on digitizing a first sample, the comparator being configured to receive a feedforward noise shaping signal for changing the threshold for digitizing a later sample of the analog input signal following the first sample.

Numerous embodiments for reading or verifying a value stored in a selected non-volatile memory cell in a vector-by-matrix multiplication (VMM) array in an artificial neural network are disclosed. The embodiments comprise various designs of input blocks for applying inputs to the VMM array during a read or verify operation and various designs of output blocks for receiving outputs from the VMM array during the read or verify operation.

Techniques are described for implementing reduced-noise pixel ramp voltage generators for image sensors. The described pixel ramp voltage generators include circuit blocks to address various conventional causes of ramp generator noise. For example, a reference current is generated. Current steering can be used to toggle between a ramp-run mode for generation of a ramp voltage, and a ramp-stop mode for stopping the generation, thereby mitigating changes in low-frequency noise components between pixel conversion cycles, or phases or such cycles. Buffer multiplier techniques can be used to isolate kickback noise of the pixel conversion comparators from components generating the ramp voltage, such as to mitigate image smearing. Some implementations include additional features, such as sample-and-hold techniques used to isolate ramp generation components from current generation component noise, slope calibration techniques to dynamically tune voltage ramp slope, reset techniques, etc.

Techniques are described for implementing reduced-noise pixel ramp voltage generators for image sensors. The described pixel ramp voltage generators include circuit blocks to address various conventional causes of ramp generator noise. For example, a reference current is generated. Current steering can be used to toggle between a ramp-run mode for generation of a ramp voltage, and a ramp-stop mode for stopping the generation, thereby mitigating changes in low-frequency noise components between pixel conversion cycles, or phases or such cycles. Buffer multiplier techniques can be used to isolate kickback noise of the pixel conversion comparators from components generating the ramp voltage, such as to mitigate image smearing. Some implementations include additional features, such as sample-and-hold techniques used to isolate ramp generation components from current generation component noise, slope calibration techniques to dynamically tune voltage ramp slope, reset techniques, etc.

A digital slope analog to digital converter device includes a capacitor array circuit, a switching circuitry, comparator circuits, encoder circuitries, and a control logic circuit. The capacitor array circuit generates a first signal according to an input signal and switching signals. The switching circuitry generates the switching signals according to an enable signal and a first valid signal in the valid signals. Each of the comparator circuits compares the first signal with a predetermined voltage, in order to generate a corresponding one of the valid signals. Each of the encoder circuitries receives the switching signals according to a corresponding one of the valid signals, in order to generate a corresponding one of sets of first digital codes. The control logic circuit performs a statistics calculation according to the sets of first digital codes, in order to generate a second digital code.

A digital slope analog to digital converter device includes a capacitor array circuit, a switching circuitry, comparator circuits, encoder circuitries, and a control logic circuit. The capacitor array circuit generates a first signal according to an input signal and switching signals. The switching circuitry generates the switching signals according to an enable signal and a first valid signal in the valid signals. Each of the comparator circuits compares the first signal with a predetermined voltage, in order to generate a corresponding one of the valid signals. Each of the encoder circuitries receives the switching signals according to a corresponding one of the valid signals, in order to generate a corresponding one of sets of first digital codes. The control logic circuit performs a statistics calculation according to the sets of first digital codes, in order to generate a second digital code.