Abstract: A pipelined current mode analog-to-digital converter, including: a plurality of stages each having a first sample and hold circuit configured to receive an analog signal having a current; the sample and hold circuit having at least first and second outputs; the first output having a current from a current copier configured to copy the analog signal; the second output having a current from a current mirror configured to mirror the analog signal; a current mode analog-to-digital converter configured to create a digital signal from the second output, the second output being connected to an input of the analog-to-digital converter; and a current mode digital-to-analog converter configured to convert the digital signal back to an analog signal, wherein an output of the digital-to-analog converter is subtracted from the first output of the sample and hold circuit.

Abstract: A system for multi-channel analog-to-digital conversion has a plurality of sampling modules, wherein each of the modules includes an input node and an output node; multiplexing circuitry configured to selectively route at least one of a plurality of electrical signals present on the output nodes to an analog-to-digital converter; and control circuitry in communication with the multiplexing circuitry, wherein the control circuitry is programmatically configured to control a sequence in which the electrical signals are routed to the analog-to-digital converter.

Abstract: A pipelined analog-to-digital converter includes a plurality of stages, each stage comprising an analog-to-digital converter (ADC) and a digital-to-analog converter (DAC). A method for increasing the accuracy of the pipelined ADC includes calibrating the ADC in each stage of the analog-to-digital converter by adjusting trip points of that ADC. Another method for increasing the accuracy of a pipelined ADC includes measuring error in an output of each the DAC; and correcting an output of the pipelined analog-to-digital converter for the measured error. These methods can be used together to further increase the accuracy of the pipelined ADC. Consequently, a pipelined analog-to-digital converter may include a look-up table containing data for correcting errors in output of each of the DACs, where trip points of the ADCs the ADCs in the stages of the pipelined converter have been calibrated to expected values.

Abstract: This method increases accuracy of a pipelined analog-to-digital converter comprising a plurality of stages, each stage comprising an analog-to-digital converter (ADC) and a digital-to-analog converter (DAC). The method includes calibrating each the ADC starting from a least significant stage until all ADCs have been calibrated using a reference digital-to-analog converter, the reference digital-to-analog converter selectively outputting values at desired trip points for each the ADC; measuring an output of each the DAC using downstream stages of the pipelined analog-to-digital converter to produce output measurements; and using the output measurements to calculate an error-corrected output of the pipelined analog-to-digital converter. The trip points are adjusted by modifying a reference current input to a comparator of each the ADC.

Abstract: An imager acquires a scene's image by pixels each of which has a digital storage device which accumulates information on a pertinent portion of the image. During image acquisition, the imager moves relative to the scene, and the contents of the digital storage devices are shifted from one pixel to another. In some embodiments, less than all bits of a digital storage device are shifted, and/or the shift is accompanied by some operation on the contents of the digital storage devices. Other features are also provided.

Abstract: An Analog-to-Digital Converter (ADC) includes analog to digital conversion circuitry configured to receive an analog signal and output a digital representation of the analog signal on a plurality of data lines; a balancing circuit configured to encode the digital representation of the analog signal on the data lines such that a total number of 1's and 0's transmitted on any given data line is the same.

Abstract: A light-to-frequency converter includes a switch (130) connected in series with a reverse-biased photodiode (120). A node (150) in the current path through the switch and the photodiode is connected to the input of a Schmidt trigger (160), whose output controls the switch. New techniques are provided for motion compensation, partial readouts, dark current elimination, non-destructive testing, and sensing the state of a memory cell.

Abstract: A pipelined current mode analog-to-digital converter, including: a plurality of stages each having a first sample and hold circuit configured to receive an analog signal having a current; the sample and hold circuit having at least first and second outputs; the first output having a current from a current copier configured to copy the analog signal; the second output having a current from a current mirror configured to mirror the analog signal; a current mode analog-to-digital converter configured to create a digital signal from the second output, the second output being connected to an input of the analog-to-digital converter; and a current mode digital-to-analog converter configured to convert the digital signal back to an analog signal, wherein an output of the digital-to-analog converter is subtracted from the first output of the sample and hold circuit.

Abstract: Exemplary sigma-delta modulators include a summing block configured to receive an input signal, a noise shaping unit configured to process an output signal of the summing block, a quantizer configured to quantize an output signal of the noise shaping unit, and a current-mode digital-to-analog converter (“DAC”) configured to convert an output of the quantizer into an analog signal and input the analog signal into the summing block in a closed loop feedback manner.

Abstract: A method of converting an analog signal to a digital signal includes comparing an input current to one or more reference currents to generate the desired digital signal. An Analog-to-Digital Converter includes a plurality of current comparators; and a plurality of current references providing reference currents to the comparators.

Abstract: A method of converting an analog signal to a digital signal includes comparing an input current to one or more reference currents to generate the desired digital signal. An Analog-to-Digital Converter includes a plurality of current comparators; and a plurality of current references providing reference currents to the comparators.

Abstract: A system for emulating characteristics of a plurality of analog-to-digital converter (ADC) architectures in the conversion of an analog signal to a digital signal. The system comprises a flash ADC for sampling the analog signal and outputting a digital representation of a sample of the analog signal, a digital-to-analog converter (DAC) for supplying the reference values to the flash ADC, and a digital signal processor (DSP) for processing the digital representation of the sample and outputting the digital signal. The digital representation is based on a comparison of the sample to reference values and comprising a number of bits of resolution. The DSP is configured to send a modifiable control signal defining the reference values to the DAC.

Abstract: An analog-to-digital converter that does not use an external clock signal to convert an incoming analog signal to a digital output signal including two or more comparators configured to receive an analog input signal, a digital-to-analog converter configured to produce a reference signal for the comparators, and asynchronous logic configured to sample comparator results and adjust a digital output signal accordingly.