Abstract: An analog-to-digital converter including analog-to-digital converting units connected in serial. The current comparator includes a current input terminal to receive a sampling current, a reference current input terminal to receive a reference current and a bit output terminal for outputting a bit signal. The current operation circuit includes a current output terminal for outputting a compared current according to the sampling current and the reference current. The operation controlling terminal selects the compared current according to the bit signal. The controlling terminal receives a clock signal to latch the bit signal. The analog-to-digital converting units output the bit signals in sequence in a period of the clock signal.

Abstract: In a conversion sequence for converting an analog input voltage into a digital signal, a redundant comparison cycle is provided to comparison cycles for performing a prescribed number of times of comparison. This redundant comparison cycle may be added after the prescribed number of comparison cycles, or may be inserted into a normal comparison cycle. Such a redundant comparison cycle adds a convergence period of a converted value to the analog input voltage. Accordingly, the final conversion result can be accurately generated even if an error is generated in the conversion sequence. As a result, a successive approximation type analog to digital converter capable of rapidly performing analog-to-digital conversion with high accuracy is implemented.

Abstract: The present invention is a pipelined analog-to-digital converter (Pipelined ADC) for converting a first analog signal to a digital data. The converter comprises at least one first stage circuit, at least one second stage circuit, a third stage circuit, and a code adder. Each of the first stage circuits has a first converting rate for converting a first analog signal to at least one digital code and generating a second analog signal. The second stage circuits are serially connected after the first stage circuit. Each of the second stage circuits has a second converting rate which is higher than the first converting rate for converting the second analog signal to at least two digital codes and generating a third analog signal. The third stage circuit serially connected after the second stage circuits is used for converting the third analog signal to at least one digital code. The code adder is used for combining the digital codes to generate the digital data.

Abstract: A digital pixel sensor architecture has a comparator located within the pixel and a frame memory located outside the pixel. The comparator is used with additional circuitry to perform analog-to-digital conversion. Replacing the analog-to-digital converter and memory of a conventional digital pixel sensor minimizes many issues associated with conventional digital pixel sensors while preserving the architecture's resistance to noise and speed.

Abstract: A processing system for a charge coupled device (CCD) or CMOS imaging system includes a correlated double sample (CDS) circuit for receiving data from an imager, a variable gain amplifier (VGA) having amplifiers of selectable current level to enable reduced data resolution in a preview display, a low power mode analog-to-digital converter (ADC) having a selectable narrow bit-width output and coupled to said VGA circuit, and a gain circuit coupled to said ADC. The single chip low-power analog front end produces digitized CCD data in either 13-bit, 12-bit or 10-bit formats at a first current level and 9-bit, 8-bit, or 6-bit formats at a second current level. The VGA amplifier includes symmetrical subcircuits which are independently actuable to enable full or reduced data resolution levels respectively for still image capture operation and video previewing on a separate preview screen.

Abstract: An A/D converter includes a capacitor type D/A conversion circuit including a capacitor array constituted of a plurality of capacitors for sampling an input potential and storing electric charge, a first resistor type D/A conversion circuit for generating a desired potential by potential division, a second resistor type D/A conversion circuit for generating a desired potential by potential division, a first signal path for adding an output of the first resistor type D/A conversion circuit to an output of the capacitor type D/A conversion circuit by capacity coupling; a second signal path for adding an output of the second resistor type D/A conversion circuit to an output of the capacitor type D/A conversion circuit by capacity coupling, and a comparing circuit for determining whether an output potential of the capacitor type D/A conversion circuit is higher or lower than an input potential, and thereby the circuit with processing time of A/D conversion being shortened can be provided.

Abstract: Differential sampler structures are provided that reduce signal distortion and current demand. The structures include first and second buffers that drive first and second capacitors and first and second switches. First and second current pumps are capacitively coupled and also cross coupled to the first and second capacitors relative to the coupling of the first and second buffers to these capacitors. As a result, signal distortion and current demand are both reduced.

Abstract: A successive approximation routine analog-to-digital converter includes a switched-capacitor circuit that samples an input voltage into a plurality of capacitors without the need for power to be dissipated by the analog-to-digital converter. A comparator, coupled to the switched-capacitor circuit, compares a voltage across the capacitors with another voltage during each of a number of iterations. A common mode voltage of the switched-capacitor circuit is boosted during at least some of the iterations. The boost may be accomplished in many different ways and may be different for each of a single-ended, a quasi-differential and fully differential versions of the analog-to-digital converter.

Abstract: The present invention relates to an analog/digital converter including an analog conversion unit including a plurality of stages having a pipelined configuration and a digital conversion unit. The digital conversion unit has digital-value storage registers, which are each provided for one of the stages. Each of the register is used for storing a digital value completing error correction for each segment, and adapted to output the digital value that corresponds to a segment number. The digital conversion unit also has an error-computation control unit, which controls the stages so that a specific one of the stages, inputs an error computation analog signal. The error-computation control unit then computes an error of the specific stage on the basis of digital-converted data computed from the digital values corresponding to segment numbers received from all the stages following the specific stage.

Abstract: This present invention is directed to a stage circuit for a pipelined analog-to-digital converter. The stage circuit includes an amplifier, a comparator, a first compensator and a second compensator, and three modes are developed for the stage circuit in signal processing: a sampling mode, a first amplifying mode and a second amplifying mode. In the sampling mode, the amplifier is inputted with an analog input signal; the comparator compares the analog input signal with a reference signal, and then generates a first digital output code. In the first amplifying mode, the first compensator selectively adds a first compensation value to the analog input signal according to the first digital output code, and then generates a first input signal; the amplifier amplifies the first input signal and then generates a first output signal; the comparator compares the first output signal with the reference signal and then generates a second digital output signal.

Abstract: In the present invention of Correlated Modulation Imaging (CMI), the weak optical image signal (and therefore the signal current) is modulated, and the signal integration direction is correlated to the modulation. Therefore, the dark and/or background current, which are not modulated, are cancelled, while the signal current is integrated. As a result, the total integration time of the signal of each pixel is increased, and its signal to noise ratio and dynamic range are improved. Besides, the CMI noise spectrum peaks at the modulation frequency, and therefore, the detector's 1/f and other low frequency noises can be suppressed. In the present invention, the method and theory of CMI, as well as the means and steps for the realization of CMI, are explicitly developed. Two versions of CMOS devices (CMI unit pre-amplifier version 1 and 3), with their circuitry design and testing data are presented as the critical component for correlated modulation imaging.

Abstract: An analog-digital converter has a sampling capacitor in which a voltage of an analog input terminal is sampled, and a digital-analog converter for performing an electric discharge of a residual voltage of the sampling capacitor at a timing prior or subsequent to an analog-digital conversion.

Abstract: An A/D conversion reference level is applied to an input of a variable offset comparator (i.e. VOC). A binary number that corresponds to the A/D conversion reference level is determined by changing a binary variable that is applied to vary the offset of the VOC until the VOC output changes states. The same procedure is applied to determine corresponding reference, binary numbers for all of the other A/D conversion reference levels. A successive approximation procedure (binary search) is then performed for a reference window in which an input analog level (to be converted into digital form) would fall, by successively applying the reference binary numbers to vary the VOC offset.

Abstract: A pseudo-differential amplifier circuit 1 is constructed from two equivalent amplifiers 2 and 3 that amplify a pair of input signals without using a differential pair. This pseudo-differential amplifier circuit 1 is used in an arithmetic unit in each of the A-D converter circuits AD1 through ADm in a parallel pipeline A-D converter 10.

Abstract: An operational amplifier for a pipeline analog-to-digital converter (ADC). The operational amplifier includes a cascaded chain of differential amplifiers, each differential amplifier including resistive-averaged common mode feedback to produce a common mode voltage for the differential amplifier, a particular differential amplifier of the chain having the highest gain of the gains of the differential amplifiers. The operational amplifier has one or more feedback paths each including a compensation capacitor to compensate the operational amplifier.

Abstract: An apparatus and method for A/D conversion is provided. The apparatus provides for multi-channel A/D conversion. It may be used in any application in which A/D conversion of either a single signal or multiple signal sources is required. Such applications include X-DSL communications. The apparatus and method allows A/D converters to be fabricated with reduced cost and power when compared with prior art designs. The A/D converter comprises a sampler, a converter and a logic. The sampler includes an input coupled with at least one analog information signal. The sampler repetitively provides at least one pre-sample together with a sample of the analog information signal. The sampling interval between the samples is substantially greater than a pre-sample interval between the pre-sample and the corresponding sample. The converter includes a bit line output and at least one input coupled with the output of said sampler.

Abstract: An A/D converter includes first to Nth stages of A/D conversion units, which are connected in series, each A/D conversion unit converting an analog input signal into a digital output signal. Each of the A/D conversion units includes a) a sample-and-hold circuit, which holds an analog input signal; b) a selector which selects one from a plurality of reference voltage signals in accordance with a digital output signal outputted from the one stage preceding A/D conversion unit; and c) a comparator which compares an output signal supplied from the sample-and-hold circuit with the reference voltage signal selected by the selector.

Abstract: An A/D converter for converting an analog input into a binary-encoded word includes a bit-weight memory storing bit weights that include maximum, mimimum, and medium weights. During a conversion step, first and second registers store lower and upper weights, and a D/A converter converts one of the upper and lower weights into an analog bit-weighting signal. A comparison device provides a comparison result indicative of a comparison between the analog input and the analog bit-weighting signal and stores the result in a third register. A multiplexer selects the upper weight when the analog input exceeds the analog bit-weighting signal and the lower weight otherwise. A subtractor subtracts, from the bit weight of a preceding conversion step, a smaller weight that is smaller than, but closest, to the previous bit weight. An adder adds the new lower weight to the smaller weight to get a new upper bit weight.

Abstract: A signal processing apparatus having: a plurality of circuit blocks each circuit block including a signal source and an output transistor adapted to receive a signal generated by the signal source at a control electrode region and output a corresponding signal from a main electrode region; and an analog/digital converter circuit adapted to sequentially process the signal from each of the plurality of circuit blocks, wherein the analog/digital converter circuit includes a reference transistor for receiving a reference level at a control electrode region and outputting a corresponding signal from a main electrode region and a digital output circuit for outputting a digital signal in accordance with a signal output from the output transistor and a signal output from the reference transistor, and wherein the output transistor and reference transistor constitute an input unit of a differential amplifier circuit including the output transistor and reference transistor.

Abstract: An A/D conversion system for an image sensor. The image sensor acquires image signals, and outputs them to a plurality of sample and hold circuits. The sample and hold circuits are grouped and are commonly actuated, in order to simplify the control circuit. Once the signals are in the sample and hold circuits, the next clock cycle commonly actuates a plurality of A/D converters which commonly convert all of those signals. During that same clock cycle, another set of sample and hold circuits may be actuated.

Abstract: An analog to digital converter for converting an analog input signal to a digital output signal, includes a first converter having a filter unit for producing at least one filter output signal by filtering the difference between the analog input signal and a feedback signal generated from a first digital output, a quantizer for producing the first digital output by quantizing the weighted sum of a first filter output from the filter unit and the analog input signal, a second converter for producing a second digital output by converting a second filter output from the filter unit, and a digital combiner for combining the first output digital signal and the second output digital signal into the digital output signal.

Abstract: A multistage analog-to-digital converter (ADC) having improved linearity is disclosed. The ADC in an illustrative embodiment includes a sampling circuit and a plurality of stages. A first one of the stages receives a sampled analog input signal from the sampling circuit, and each of the stages operates to generate an output corresponding to one or more bits of a digital output signal representative of the analog input signal. Each of at least a subset of the stages has associated therewith at least one amplifier circuit, e.g., an output analog residue amplifier, having at least one sampling component and at least one feedback component. The sampling component and the feedback component are periodically swapped to reduce gain error between one or more of the stages so as to provide improved linearity for the ADC.

Abstract: An analog-to-digital converter including a first module of the type having a series of processor stages, each of the stages performing two conversions of the signal output by the preceding stage, firstly an analog-to-digital conversion and secondly a digital-to-analog conversion, followed by subtracting the signal obtained from the output signal of the preceding stage to provide the analog output signal of the stage. The first module further assembles together the signals digitized by each stage (S1, . . . , Si) so as to provide an assembled digital signal (SN(nT) which represents the input signal (e(nT) of the converter in digital form.

Abstract: A system and method for converting an analog input signal to a N-bit digital output signal. The invention comprises generating a plurality of reference voltage signals; pre-amplifying, separately, a difference between each of the plurality of reference voltage signals and an analog input signal using a plurality of cascaded, differential, switched-capacitor circuits to output a plurality of pre-amplified difference signals; and determining a zero-crossing result for each of the plurality of pre-amplified difference signals. Then one of a binary 1 and a binary 0 are assigned to each of the compared, pre-amplified signals. The binary 1's and 0's are encoded as an M-bit encoded signal, which is then decoded to output an N-bit digital output signal, wherein M is less that or equal to N.

Abstract: Quantizers included in an analog-to-digital converter each compare an input analog voltage with a reference voltage to convert the analog voltage to digital data and output a voltage representative of a difference between the analog voltage and a voltage corresponding to the digital data. In each quantizer includes a comparator comparing the analog voltage with the reference voltage to output a result of comparison. An amplifier amplifies a voltage representative of a difference of the analog voltage from the reference voltage. Another amplifier inverts the voltage representative of the difference of the analog voltage from the reference voltage and amplifies the inverted voltage. A couple of switches are respectively connected to the one and the other amplifier for selecting either one of the output voltages of the amplifiers in accordance with the result of comparison.

Abstract: A RSD analog to digital converter has an RSD stage that in turn has a switched capacitor integrator (SCI). The SCI uses an operational amplifier. A capacitor, which operates as a offset compensation capacitor, is precharged to the offset voltage of the operational amplifier during a precharge phase. The next phase switches this offset compensation capacitor in the path of the capacitors which are used to perform the integration. The effect is that the offset of the operational amplifier is corrected by the use of the compensation capacitor that had been precharged to the offset voltage during the previous phase.

Abstract: An A/D converter comprises: a differential amplifier row for amplifying differential voltages between an analog input voltage and reference voltages; a first sample/hold circuit row for sampling/holding the individual differential voltages amplified; a second sample/hold circuit having a pair of second and third sample/hold circuits connected in parallel to each output of the first sample/hold circuit row, thereby performing alternate sampling; a plurality of comparators for determining whether the individual differential voltages held by the first sample/hold circuit row are positive or negative; and an encoder for outputting digital code corresponding to the outputs of the comparators.

Abstract: There is disclosed, for use in an analog to digital (ADC) converter, an ADC stage that receives a differential analog input signal, quantizes the differential analog input signal to a plurality of digital bits, and generates an output residue signal corresponding to a quantization error of the differential analog input signal.

Abstract: A double comparison successive approximation A/D converter. The converter compares the value with upper and lower limits. The bit values are not set unless the value is distant from the compared value. Otherwise, the value of the bit is held until later when the bit does fall outside the limits.

Abstract: An analog computation system which forms a hybrid between analog and digital computation. The analog signal is divided into a plurality of separated analog signals, each of the different analog signals collectively representing the original analog signal, and each having less resolution then the total desired resolution. A number of different analog computation elements carry out a mathematical function on the separated signal. Different stages may be provided, and a signal restoration device may be provided between the different stages.

Abstract: A method is provided for defining programmed values of the boost and cut-off frequency parameters of a low pass filter of pre-equalization, of a read channel for a magnetic medium mass memory device, to ensure optimal functioning conditions of the adaptive filter of final equalization. The method includes pre-programming instantaneous digital values of the boost and cut-off frequency parameters of the low pass filter of pre-equalization for each magnetic medium, as a function of purposely sensed instantaneous operating parameters of the adaptive filter that carries out the definitive equalization of the signal during a trim scanning of the magnetic medium.

Abstract: A pipelined analog-to-digital converter system (10) is responsive to an analog input signal (18). The system includes four pipeline stages (11-14), which each produce a respective digital output (26-29) that is coupled to a combining circuit (16). The combining circuit generates the digital output (41) of the system. Each pipeline stage includes an analog-to-digital converter (101), which generates the digital output for that stage. A shuffler circuit (103) randomly shuffles the bits of this digital output, in order to generate shuffled switching signals, which in turn are used to control electronic switches (206-209, 211-214) associated with several capacitors (C1-C4). By randomly shuffling the switching signals, the effects caused by variation of any capacitor from an ideal value are randomized. This avoids nonlinearity such as harmonic distortion in the analog output signal (21) from that stage.

Abstract: A pipelined analog-to-digital converter includes a first stage 700 of an analog-to-digital converter having a first resolution. The first stage 700 includes a three capacitor switched capacitor circuit. The analog-to-digital converter further includes one or more subsequent analog-to-digital converter stages 200. The first and subsequent stages 700 and 200 are pipelined together to provide a digital output signal.

Abstract: A non-sampling cascaded current mode analog-to-digital converter is formed of cascaded threshold detector bit cells driven by a transconductance amplifier for substantially instantaneously propagated current mode operation. A front end stage receives an input voltage representative of the quantity to be digitized, and outputs a pair of currents to N−1 cascaded, identically configured threshold comparator-based bit cells, N being the number of bits of resolution of the converter. A bit cell resolves a digital bit and couples a pair of output currents to the next bit cell. The N−1th bit cell in the cascaded architecture is configured to provide both the next to least significant bit and the least significant bit.

Abstract: There is provided an A/D converter such that a successive approximation register has a plurality of A/D registers each corresponding to one of A/D inputs, and that a capacitor in a comparator is charged by a voltage determined based on a value held in an A/D register corresponding to an A/D input to be A/D converted before starting A/D conversion of the A/D input, thereby reducing noise generated at the time of selecting A/D inputs to enhance A/D conversion accuracy.

Abstract: A current mode pipelined analogue to digital converter (ADC) has a plurality of serially connected conversion stages. Each conversion stage has an input (40) for receiving a sampled and held current which is connected via a switch (S41) to a first current memory (M42) and via a switch (S40) to a second current memory (M41). The output of the second current memory (M41) is fed via a switch (S44) to one input of a summing junction (46). The output of the first current memory (M42) is fed via a switch (S42) to the input of a comparator (L44) whose output is clocked into a latch (L44) whose Q output is connected to an output (45) as the digital result of the conversion. The Q output of the latch (L44) is also connected to a digital to analogue converter (46) whose analogue output is fed to a second input of the summing junction 46 via a switch (S43) to form the analogue residue signal for application via output (47) to the next conversion stage in the pipeline.

Abstract: An apparatus and method for A/D conversion is provided. The apparatus provides for multi-path multi-channel (MPMC) pipelined A/D conversion. Unlike prior art designs in which the handling of multiple channels requires a linear increase in the associated circuitry and components, the current design scales for multiple channel A/D conversion with less than linear scalability. The A/D converter comprises a plurality of stages and interfaces between adjacent columns of the stages. The stages each include an input, a first output, and a second output. Each of the stages is responsive to an input signal applied to the input to output at the first output a bit signal corresponding to at least one significant bit of the input signal and to output at the second output a residue signal corresponding to a difference between the input signal and the bit signal. The stages are arranged in columns.

Abstract: In an analog-to-digital conversion circuit having a multistage pipeline structure, a plurality of stages of operational amplifiers are provided in a circuit of each stage. In the circuit of each stage, an analog input signal outputted from the circuit of the precedent stage is supplied to the precedent operational amplifier and a sub A-D converter. The sub A-D converter supplies the result of A-D conversion to a D-A converter. A subtraction circuit performs subtraction of an output of the precedent operational amplifier and a result of D-A conversion of the D-A converter. The subsequent operational amplifier amplifies an output of the subtraction circuit and supplies the same to the circuit of the subsequent stage. In each operational amplifier, a first switch is connected between a first input node and a first output node, a second switch is connected between a second input node and a second output node, and a third switch is connected between the first and second output nodes.

Abstract: A pipeline analog to digital (A/D) converter for converting an analog input signal into a digital representation of the analog signal. The pipeline A/D converter has a sample and hold stage, the sample and hold stage sampling and holding the analog input signal and outputting a sampled and held signal. The pipeline A/D converter also has a first analog signal converter stage, the first analog converter stage producing a digital output based on the sampled and held signal, from which a most significant bit of the digital representation of the analog input signal is derived. The first analog converter stage produces a residue signal based on a comparison of the analog input signal and an analog representation of the digital output.

Abstract: An analog-to-digital or digital-to-analog system contains a converter (706). The converter is supplied with a clock signal (CLK1) at a frequency fs derived from a crystal of a frequency fs/N. The frequency fs is derived from the fs/N crystal frequency by using an edge-triggered clock multiplier 705 which multiplies the crystal frequency by the factor N. The result is a low-cost clock solution that incorporates clock jitter around a localized frequency of fs/N. Sigma delta processing circuitry (702) is then used to place a null (e.g., low gain area) in the quantization noise at the same frequency where clock jitter noise is high in order to cancel the adverse cumulative effects of these two types of noise.

Abstract: A/D conversion of a current input is performed with integrate-and-fire spiking neurons. Techniques that upcount or downcount the number of spikes fired by one neuron in a time period established by another neuron yield quantized estimates of analog charge residues created by the input current. Recursive application of alternate upcounting and downcounting operations yields successively finer quantization estimates that are terminated by an error-correction operation to obtain the least significant bit of the conversion. A spike-based hybrid state machine (HSM) employing both analog and digital elements is configured to create a 2-step or a successive-subranging analog-to-digital converter. The speed of the conversion is augmented in a pipelined topology. In the HSM, a spike-triggered finite state machine (FSM) controls the input currents to the spiking neurons and is in turn controlled by spikes arising from these neurons.

Abstract: A system and method for calibrating an analog to digital (A/D) converter. The A/D converter includes an internal D/A converter, wherein the internal D/A converter includes a plurality of current generators, and wherein one or more of the current generators may produce linearity errors in the A/D converter. The A/D converter includes a switching element connected to the internal D/A converter. During calibration, the switching element operates to adjust connections to the current generators in the internal D/A converter one or more times according to different switching patterns, thereby causing different ones of the current generators to be stimulated by an input to the A/D converter. This avoids the necessity of using a complex and costly waveform generator input during calibration, which would normally be required to ensure that all of the current generators in the internal D/A converter are stimulated. Rather, a much simpler input can be used in calibrating the A/D converter, thereby reducing cost.

Abstract: A pipeline analog-to-digital conversion system (10) includes a plurality of cascaded subconverter stages (12) and a digital correction unit (16). Each subconverter stage (12) includes an n-bit analog-to-digital converter (26), an n-bit digital-to-analog converter (28), and an arithmetic unit (32). The n-bit analog-to-digital converter (26) generates a second intermediate digital signal (18) as a function of a first input analog signal (24) and a corresponding first intermediate digital signal (18) received from a previous stage (12).

Abstract: An Analog-to-Digital Converter (ADC) contains two pipeline stages that operate in parallel on two different analog samples. Each pipeline stage includes two sub-stages. Each sub-stage has a low-resolution ADC element and a low-resolution DAC element. The ADC element converts the analog voltage input to the sub-stage into B digital bits, where B is a low number such as 1, 1.5, or 2. These digital bits are re-converted back to an analog DAC voltage by the DAC element. A subtractor then subtracts the analog DAC voltage from the sub-stage's analog input voltage to produce a difference voltage that represents the quantization error of the ADC/DAC elements. A multiplying amplifier multiplies the difference voltage by 2B to generate an output voltage to the next sub-stage. Each high-level pipeline stage acts as a recycling ADC, having a feedback switch that connects the output of the last sub-stage to the analog input of the first sub-stage.

Abstract: A pipeline analog-to-digital conversion system (10) includes a plurality of cascaded subconverter stages (12) and a digital correction unit (18). Each subconverter stage (12) includes an n-bit analog-to-digital converter (36), an n-bit digital-to-analog converter (38), and an arithmetic unit (42). Arithmetic unit (42) simultaneously samples a second input analog signal (34) and produces an output analog signal (44) representative of the difference between a first input analog signal (32) and a corresponding intermediate analog signal (40).

Abstract: An integrated circuit includes a variable bit-depth successive approximation analog-to-digital converter. The variable bit-depth successive approximation analog-to-digital converter can select from at least two clock signals of different frequencies to drive the variable bit-depth successive approximation converter for each bit depth application. Within each bit-depth application, the converter may employ more than one clock frequency.

Abstract: Digital to Analog convertors (DAC's) are prone to mismatch noise, particularly in DAC structures using unequally weighted segments. A digital to analog converter, for use in a data conversion system, for converting a digital input to analog output and having features for reducing mismatch noise comprises a plurality of selectable segments, at least two of which have a first weighting factor and at least two of which have a second weighting factor. The segments when selected are connected to a reference signal, with the output for each segment, when selected, being proportional to the weighting factor of the segments. Selection means select segments based on the digital input. Summing means add the output from each selected segment to produce an analog output. The number of segments having the second weighting factor is equal to at least twice the ratio of the first and second weighting factors less one.

Abstract: A common-mode sensing circuit (504) of a clocked differential amplifier (602) includes a refresh circuit (604) which precharges a capacitance during a first clock phase (P.sub.1) and discharges the capacitance to drive the outputs (514, 516) of the differential amplifier (602) to a desired common-mode voltage (V.sub.AGO) during a second clock phase, which increases the output loading during the second clock phase (P.sub.2). A load balancing circuit (606) selectively switches a load to the outputs (514, 516) during the first clock phase (P.sub.1) to match the load produced by the refresh circuit (604) during the second clock phase (P.sub.2).

Abstract: A capacitively-coupled successive approximation analog-to-digital converter utilizes a capacitively coupled multiplying digital to analog converter to generate a succession of voltages which are compared to the input voltage to be digitized. The capacitively coupled multiplying digital to analog converter generates the required succession of analog voltage levels utilizing very low power in response to digital signals. A double-sided version of the invention processes differential inputs with improved common-non-ideality mode rejection.

Abstract: A digitally compensated analog-to-digital converter (ADC) provides improved linearity by generating calibration values having higher resolution than the output signal generated during a normal conversion. During a calibration value generation operation, the converter performs a normal conversion, then performs an additional conversion, thereby generating a high resolution calibration value which is then rounded and stored in a memory device. The converter includes a flash ADC which converts an analog input signal received through a multiplexer and sample-hold amplifier to a digital signal. The flash ADC provides control signals to a multibit digital-to-analog converter which generates the analog reconfiguration signal during multi-stage conversions. A digital correction circuit receives the digital signals from several multi-stage conversion and generates a corrected signal.