Abstract: A switched-capacitor circuit is disclosed. The switched-capacitor circuit includes a comparator having a first and second input, a first and second sampling capacitor, and a first and second switching circuitry. The first switching circuitry charges the first and second sampling capacitor with an input signal. The second switching circuitry selectively couples the first sampling capacitor with a reference voltage and selectively couples the second sampling capacitor and the first and second input of the comparator to a common voltage. The comparator performs a compare of the input signals against the reference voltage, and outputs a signal.

Abstract: In one embodiment, an apparatus includes a first capacitor system and a second capacitor system. Each capacitor system comprises one or more engaged capacitors from respective pluralities of selectively engagable capacitors. The first capacitor system and second capacitor system are respectively selectively coupled to a first reference voltage and a second reference voltage. The apparatus further includes a switch configured to transfer charge between the first capacitor system and the second capacitor system when the switch is closed such that the first capacitor system and the second capacitor system each store the same first voltage. The apparatus further includes a node coupled to the first capacitor system, the second capacitor system, and a first input of a differential amplifier of an analog to digital converter. The node is configured to bias the differential amplifier to the first voltage.

Abstract: A Successive-Approximation Register Analog-to-Digital Converter (SAR-ADC) predicts compensation values for use in a future cycle. A compensation value is applied to capacitors in a calibration Y-side capacitor array to compensate for capacitance errors in a binary-weighted X-side capacitor array. Two compute engines pre-calculate predicted-0 and predicted-1 compensation values for a next bit to be converted. At the end of the current cycle when the comparator determines the current bit, the comparator also controls a mux to select one of the two predicted compensation values. Thus the compensation value is available at the beginning of the next bit's cycle, eliminating a long calculation delay. The compensation value for the first bit to be converted, such as the MSB, is calculated during calibration. Compensation values for other bits are data-dependent. Calibration values are accumulated during calibration to generate the first conversion compensation value for the first bit to be converted.

Abstract: An ADC module includes an analog to digital converter coupled with an analog bus, wherein the an analog to digital converter comprises a main sample and hold capacitor; and a plurality of additional sample and hold capacitances which can be programmably coupled in parallel with said main sample and hold capacitance.

Abstract: In one embodiment, an apparatus comprises a first capacitor system and a second capacitor system. Each capacitor system is removably coupled to the same portion of an analog to digital converter (ADC) and the same sensing circuit. Each capacitor system stores charge received through the sensing circuit when coupled to the sensing circuit and provides the charge received through the sensing circuit to the ADC for conversion into a digital value when coupled to the ADC. When the control signals are in a first state, the first capacitor system receives charge through the sensing circuit and the second capacitor system is coupled to the portion of the ADC. When the one or more control signals are in a second state, the second capacitor system is coupled to the sensing circuit to receive charge through the sensing circuit and the first capacitor system is coupled to the portion of the ADC.

Abstract: The configurations and adjusting method of a successive approximation analog-to-digital converter (SAR ADC) are provided. The provided SAR ADC includes at least one capacitor with a first and a second terminals, and a plurality of bits, each of which is connected to the at least one capacitor, wherein the first terminal receives an input signal, and the second terminal selectively receives one of a first and a second reference voltages, and a first comparator receiving an adjustable third reference voltage and a first voltage value generated by the input signal, wherein a connection of the second terminal of each the capacitor of the capacitor array is switched when the first voltage value is larger than the third reference voltage.

Abstract: An SAR-ADC includes input and reference terminals, first and second capacitor sets, a dummy capacitor, a comparator, a switch, and a logic. The first and second capacitor sets include first and second capacitors, respectively. The first capacitor has a first capacitance. The second capacitor has a second capacitance. The dummy capacitor has a third capacitance. The comparator compares an output voltage with a ground voltage and outputs a digital output code in accordance with a difference between the output and ground voltages. The switch is connected among the first capacitors of the first and second capacitor sets, and the reference terminal. The logic turns the switch based on the digital output code. The input terminal is located between the first and second capacitors of the first capacitor set. The second capacitor of the first capacitor set is located between the first and second capacitors of the second capacitor set.

Abstract: A method and apparatus for operating an analog-digital converter for converting an input signal into a multibit output in one conversion cycle. The method includes loading a capacitor array by applying a given input signal potential, evaluating a sampling potential provided by the capacitor array in a number of consecutive decision steps performed by at least two decision latches and changing the sampling potential by switching the capacitor array for each decision step based on a result of the step of evaluating the sampling potential, where the step of evaluating at least one of the decision latches performs the evaluating for two decision steps.

Abstract: A capacitive-to-digital converter is provided which includes: sensor, offset and reference capacitors, an integrator circuit and a demodulation circuit. The sensor capacitor is switched according to a first clock and the offset capacitor according to a second clock, which has a higher switching frequency. The reference capacitor is switched according to a return signal from the converter's output. The integrator circuit includes an integrator capacitor, and has first and second nodes, with the sensor, offset and reference capacitors each being switched to the first and second nodes based on the respective first clock, second clock or return signal. The demodulation circuit receives and converts output of the integrator circuit into a digital output. The higher frequency clocking of the offset capacitor allows for a reduction in capacitance of the offset, reference or integrator capacitor, and the multiclocking of the converter allows for use of a multireferencing to the sensor capacitor.

Abstract: An arrangement for digital measuring a capacitive sensor is provided with a charge balance frequency converter having an operational amplifier with an inverting input, a noninverting input and an output. Between the output and the inverting input an integrating capacitor is connected, and the noninverting input is connected with a reference potential. The arrangement provides a simple switched capacitor architecture for measuring the sensor capacitance, which tolerates grounded sensor capacitors, and which is not affected by the shunt resistance. The value of the shunt resistance is determined at the same time. The arrangement makes use of a two frequency measurement of the capacitor resistance combination by using the charge balancing procedure followed by a calculation based on the results of two conversions and the ratio of the clock frequencies of the first and second conversion.

Abstract: A SAR ADC, used for converting an analog input into an N-bit digital output in a conversion phase, includes: three comparators, each two capacitor sub-arrays, coupled to the three comparators respectively, wherein the two capacitor sub-arrays are used for sampling the analog input and providing two inputs for the corresponding comparator; and an SAR logic, coupled to the three comparators and the three capacitor arrays, for, in each conversion sub-phase, coupling two selected capacitors of each capacitor sub-array to a set of determined reference levels, coupling two capacitors, which were selected in a preceding conversion sub-phase, of each capacitor sub-array to a set of adjusted reference levels obtained based on a set of data outputted from the three comparators in a preceding conversion sub-phase, and then generating two bits of the N-bit digital output by encoding a set of data outputted from the three comparators.

Abstract: An SAR ADC capable of reducing energy consumption, including a voltage selecting circuit for configuring a capacitor circuit to form a first equivalent capacitor having a capacitance of (2m?1)C, a second equivalent capacitor having a capacitance of (2n?2m+1)C, a fourth equivalent capacitor having a capacitance of (2m?1)C, and a fifth equivalent capacitor having a capacitance of (2n?2m+1)C, wherein, the first equivalent capacitor has one terminal coupled to a reference voltage or a ground voltage, and the other terminal coupled to a positive input end of a comparator; the second equivalent capacitor is coupled between a common mode voltage and the positive input end; the fourth equivalent capacitor has one terminal coupled to the ground voltage or the reference voltage, and the other terminal coupled to a negative input end of the comparator; and the fifth equivalent capacitor is coupled between the common mode voltage and the negative input end.

Abstract: A control circuit connects a capacitor to an input terminal and an output terminal of an operational amplifier and applies a signal charge to charge the capacitor with a switch being turned off. Thus, a conversion voltage corresponding to the signal charge is outputted from the operational amplifier. The control circuit then sets charges, which correspond to the conversion voltage, in capacitors and reallocates the charges among the capacitors by connecting non-common electrodes of the capacitors to either one of a plurality of reference voltage lines in accordance with a conversion result of an A/D conversion circuit with the capacitor being connected to the input terminal and the output terminal of the operational amplifier. The control circuit thereafter performs, a number of times, charge setting, initialization and subsequent charge reallocation in accordance with a residual voltage outputted from the operational amplifier.

Abstract: In an A/D converter, a first analog signal which is input to an input terminal in a state in which the input terminal and a reference voltage line are connected via a first capacitor is converted into digital data when a reference signal is supplied to the reference signal line in a state in which the reference signal line and a first input terminal of a comparator are connected via the first capacitor. A second analog signal which is input to the input terminal in a state in which the input terminal and the reference voltage line are connected via a second capacitor is converted into digital data when the reference signal is supplied to the reference signal line in a state in which the reference signal line and the first input terminal of the comparator are connected via the second capacitor.

Abstract: A continuous-time sigma-delta analog to digital converter (CTSD ADC) includes a comparator that samples the time integral of an analog signal at each rising edge and falling edge of a sampling clock. A feedback block, operating as a digital to analog converter, receives the outputs of the comparator and generates corresponding analog signals also at each rising and falling edge of the sampling clock. The feedback blocks are implemented as either switched-resistor or switched-current circuits. High signal-to-noise ratio (SNR) is achieved in the CTSD ADC without the need to use very high sampling clock frequencies. Compensation for excess loop delay is provided using a local feedback technique. In an embodiment, the sigma delta modulator in the CTSD ADC is implemented as a second order loop, and the comparator as a two-level comparator.

Abstract: A stage of a pipeline analog-to-digital converter (ADC) is provided according to embodiments of the present invention. The stage of the present invention has double-amplifier architecture and uses level-shifting technique to generate a residue of the stage. The amplifiers of the stage are implemented in two different split paths, thereby to generate a relatively coarse amplification result and a relative fine amplification result. The relatively coarse amplification result is used to level-shift the output level of the amplifier. As a result, the stage of the present invention can have a correct residual by using amplifiers of moderate quality.

Abstract: A singled-ended, successive approximation register analog-to-digital converter convert an analog input voltage to a digital representation comprising m upper order bits and a number of lower order bits. The SAR ADC comprises SAR logic, a resistive network, multiple switches, and first and second LSB capacitors. The switches also comprises two sets of switches coupled to the resistive network, each set of switches is configured to couple a selected tap to each of the first and second LSB capacitors. When determining the lower order bits, the SAR logic is configured to control the sets of switches to change the first and second taps from one cycle in which one of the lower order bits is determined to a next cycle in which the next of the lower order bits is determined so that the voltage of both taps changes by a decreasing amount with each succeeding bit being determined.

Abstract: Embodiments of the present disclosure may provide a charge redistribution DAC with an on-chip reservoir capacitor to provide charges to the DAC in lieu of traditional external reference voltages. The DAC may include the on-chip reservoir capacitor having a first plate and a second plate, an array of DAC capacitors to generate a DAC output, and an array of switches controlled by a DAC input word to couple the DAC capacitors to the reservoir capacitor. The charge redistribution DAC may further comprise a first switch connecting the first plate to an external terminal for a first external reference voltage, and a second switch connecting the second plate to an external terminal for a second external reference voltage. One embodiment may provide an ADC that includes the charge redistribution DAC.

Abstract: A successive approximation register (SAR) analog-to-digital converter (ADC) is disclosed. A first and second capacitor DACs receive a first and second input signals respectively. A first coarse comparator compares an output of the first capacitor DAC with a window reference voltage, a second coarse comparator compares an output of the second capacitor DAC with the window reference voltage, and a fine comparator compares the output of the first capacitor DAC with the output of the second capacitor DAC. A SAR controller receives outputs of the first and second coarse comparators to determine whether the outputs of the first and second capacitor DACs are within a predictive window determined by the window reference voltage. The SAR controller bypasses at least one phase of analog-to-digital conversion of the SAR ADC when the outputs of the first capacitor DAC and the second capacitor DAC are determined to be within the predictive window.

Abstract: A ?? analog-to-digital converter is disclosed. In a sampling phase, first and second input signals of an analog differential input signal pair are sampled on respective first and second sampling capacitors and first and second reference signals are sampled on respective third and fourth sampling capacitors. During a subsequent sample/integration phase, the first and second input signals are sampled on the respective second and first sampling capacitors and the first and second reference signals are sampled on the respective fourth and third sampling capacitors. In addition, charges present on the sampling capacitors are transferred to a pair of integrating capacitors that form part of a differential integrator. A quantizer circuit responsive to the integrator output provides the digital output of the converter. Thus, correlated double sampling is carried out, with dynamic element matching of the sampling capacitor being a further option.

Abstract: Systems and methods are provided for converting analog data to digital data that can include a discharge capacitor coupled to a voltage source. The voltage source supplies an initial data charge to the discharge capacitor; an amplifier coupled to the discharge capacitor; a divider circuit coupled to the amplifier; and a comparator coupled to the amplifier and the divider circuit. The divider circuit includes a first capacitor, a second capacitor, and a switch that is operated to alternately divide a remaining charge Q by 2N using the first and second capacitors until the remaining data charge Qin at the amplifier is below a threshold value in the process of converting analog data to digital data.

Abstract: An analog-to-digital (AD) converter device, includes: a capacitive digital-to-analog converter (DAC) including a reference capacitor group having capacitors which are weighted with a ratio, one terminal of each of the capacitors being coupled to a common signal line, the other terminal of each of the capacitors being coupled to one of reference power supplies via one of switches; a comparator to compare a voltage of the common signal line with a reference voltage; a successive approximation routine circuit to control the switches based on a comparison result of the comparator; an offset correction circuit to correct an offset of the comparator; and a DAC correction circuit to correct an error in a voltage change of the common signal line, the offset correction circuit and the DAC correction circuit performing a correction so that a residual offset of the comparator and a residual error of the capacitive DAC cancel.

Abstract: Successive approximation Analog-to-digital converters (ADCs) and related methods are disclosed. A successive approximation ADC includes a comparator with a comparator output and inputs coupled to a common model signal and a compare input. Control logic generates one or more control signals responsive to the comparator output. A capacitor array includes first sides of capacitors operably coupled to an array output. The capacitor arrays selectively couples each of second sides of the capacitors to an analog input signal and one or more input reference signals responsive to the one or more control signals. A voltage limiter is operably coupled between the array output and the compare input of the comparator and limits a voltage on the compare input to within a predefined range relative to the array output. The successive approximation ADC may also be configured differentially with a second comparator and a second voltage limiter.

Abstract: In one embodiment, an apparatus includes a first capacitor system and a second capacitor system. Each capacitor system comprises one or more engaged capacitors from respective pluralities of selectively engagable capacitors. The first capacitor system and second capacitor system are respectively selectively coupled to a first reference voltage and a second reference voltage. The apparatus further includes a switch configured to transfer charge between the first capacitor system and the second capacitor system when the switch is closed such that the first capacitor system and the second capacitor system each store the same first voltage. The apparatus further includes a node coupled to the first capacitor system, the second capacitor system, and a first input of a differential amplifier of an analog to digital converter. The node is configured to bias the differential amplifier to the first voltage.

Abstract: In one embodiment, an apparatus comprises a first capacitor system and a second capacitor system. Each capacitor system is removably coupled to the same portion of an analog to digital converter (ADC) and the same sensing circuit. Each capacitor system stores charge received through the sensing circuit when coupled to the sensing circuit and provides the charge received through the sensing circuit to the ADC for conversion into a digital value when coupled to the ADC. When the control signals are in a first state, the first capacitor system receives charge through the sensing circuit and the second capacitor system is coupled to the portion of the ADC. When the one or more control signals are in a second state, the second capacitor system is coupled to the sensing circuit to receive charge through the sensing circuit and the first capacitor system is coupled to the portion of the ADC.

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: An analog-to-digital converter includes a plurality of sequentially cascaded stages, each stage including an amplifier and four copies of a circuit block including a flash and capacitors, in which the four copies of the circuit block operate interleavingly in a respective sample mode, pre-gain mode, gain mode, and reset mode of the circuit block, the copies of the circuit block in the sample mode, pre-gain mode, and reset mode are decoupled from the amplifier, and the copy of the circuit block in the gain mode is coupled to the amplifier to produce an output for a next following stage.

Abstract: The present invention is related to an analog to digital converter circuit. The circuit comprises at least one input node for applying an analog input voltage signal (Vin), means for sampling said analog input voltage signal, a first array of capacitors arranged for receiving the sampled analog input voltage signal, a digital delay line connected to the first array of capacitors and arranged for being enabled by a clock generator and for generating a staircase or slope function by means of the first capacitor array, taking into account the sampled analog input voltage signal, a comparator arranged for comparing a converted signal with a reference voltage (Vref), said converted signal being a version of said sampled analog input voltage converted according to said staircase or slope function, and for generating a stop signal based on the comparison result thereby latching the digital delay line and thereby acquiring the digital code.

Abstract: An A/D converter includes a capacitive DAC configured to perform conversion of high-order bits by receiving a differential signal, a resistive DAC configured to perform conversion of low-order bits, a resistive correction DAC configured to operate to correct the capacitive DAC, and a comparator. The capacitive DAC includes a positive-side capacitive DAC and a negative-side capacitive DAC operating in a complementary fashion, and the comparator, which includes a plurality of differential circuits, is configured to compare output potentials of the positive-side capacitive DAC and the negative-side capacitive DAC. The positive-side capacitive DAC and the negative-side capacitive DAC include first capacitive elements each formed from interconnect layers excluding an uppermost interconnect layer, and the comparator includes second capacitive elements each provided between adjacent ones of the differential circuits and formed from interconnect layers including the uppermost interconnect layer.

Abstract: Systems and methods are provided for converting analog data to digital data that can include performing N successive analog subtractions from an initial data charge Qin. The analog subtractions are performed using an amplifier coupled to a discharge capacitor and a divider circuit coupled to an input of the amplifier. The divider circuit includes a first capacitor, a second capacitor, and a switch to alternately divide a remaining charge Q by 2N between the first and second capacitors until the remaining charge Qin at the amplifier is below a threshold value. A compensating circuit compensates for fluctuations in the charge held by the first and second capacitors due to operation of the switch.

Abstract: Systems and methods are provided for converting analog data to digital data that can include a discharge capacitor coupled to a voltage source. The voltage source supplies an initial data charge to the discharge capacitor; an amplifier coupled to the discharge capacitor; a divider circuit coupled to the amplifier; and a comparator coupled to the amplifier and the divider circuit. The divider circuit includes a first capacitor, a second capacitor, and a switch that is operated to alternately divide a remaining charge Q by 2N using the first and second capacitors until the remaining data charge Qin at the amplifier is below a threshold value in the process of converting analog data to digital data.

Abstract: An analog-to-digital converter includes: weighted capacitors connected to each other at one ends thereof, having a capacitance value weighted at a predetermined ratio, and including a variable capacitance capacitor capable of reducing the capacitance value; a comparator including an input to which the one ends of the weighted capacitors are coupled; switches that connect the other ends different from the one ends to any of an input terminal into which an input signal is input, a reference voltage source used for successive approximation of the input signal, a ground, and an open terminal; a successive approximation controller that controls the switches to sample the input signal onto the weighted capacitors, and use the reference voltage source to generate a comparative voltage for the successive approximation, to thereby execute a successive approximation; and a capacitance controller that controls the switches to reduce a capacitance value of the variable capacitance capacitor.

Abstract: Analog to digital conversion is performed by sampling an input voltage followed by AD conversion of the sampled voltage. In the sample and hold circuit a differential amplifier output voltage is generated between the first and second output of a differential amplifier in response to the sampled input voltage. A conversion polarity is selected by connecting the one output or the other of the differential amplifier to a circuit node in an AD conversion circuit using a first or second switch. These switches from both outputs of the differential amplifier to the same circuit node of the AD conversion circuit are both made conductive simultaneously prior to making the selected one of the first and second switch conductive. In this way, the amplifier output voltage is reset without requiring a dedicated switch just for this purpose.

Abstract: A method for operating an analog-digital converter including a number of charging units, each comprising a switchable capacitor and an associated reference potential source, includes evaluating a comparison potential in successive decision steps to obtain a comparison result; and successively switching one of the charging units following a previous one of the decision steps, wherein, depending on the obtained comparison result, the comparison potential is changed by the one respective charging unit by connecting the associated reference potential source to the switchable capacitor, wherein in two of the successive switching steps different reference potentials are applied to the switchable capacitor.

Abstract: Various embodiments of this disclosure may describe a two-stage ADC circuit, and a time-interleaved system based on the two-stage ADC circuit. The two-stage ADC circuit may include a SAR converter for the first stage and a charge based TDC for the second stage. The two-stage ADC circuit may be used in high performance serial I/O applications. Other embodiments may be disclosed and claimed.

Abstract: An analog-digital converter includes a decision unit configured to evaluate a comparison potential in a decision step to obtain a comparison result; a number of charging units each comprising a switchable capacitor and an associated reference potential source, wherein each charging unit is configured to change the comparison potential by connecting the reference potential source to the switchable capacitor; and a control unit configure to successively switching one of the charging units following a previous decision step wherein, depending on the obtained comparison result the comparison potential is applied with a predetermined charge by the one respective charging unit, and wherein at least two of the charging units have an associated reference potential source providing different reference potentials.

Abstract: The present invention provides an n-bits successive approximation register (SAR) analog-to-digital converting (ADC) circuit, comprising: an n-bits SAR control logic, a p-type capacitor network including a DACp array and a sampling capacitor CSp, an n-type capacitor network including a DACn array and a sampling capacitor CSn; and a comparator for comparing outputs from the p-type capacitor network and the n-type capacitor network, wherein a power supply and ground are directly connected to the p-type capacitor network and the n-type capacitor network without using reference voltages produced by a reference voltage generator. The n-bits SAR control logic comprises n shift registers, n bit registers, and a switching logic. The comparator comprises a first pre-amplifier, a second pre-amplifier and a dynamic latch. Alternative, the comparator comprises a four-input pre-amplifier and a dynamic latch.

Abstract: A successive approximation register (SAR) analog-to-digital converter (ADC) includes a first capacitor array, a first input capacitor, a first switch module, a second capacitor array, a second input capacitor, a second switch module, a comparator and a SAR controller. The SAR ADC is operated under sampling phases and amplifying phases many times to perform amplifying operations and ADC operations upon input signals to generate digital output data. In addition, because the SAR ADC has both an amplification function and an ADC function, a circuit utilizing the SAR ADC does not require an additional active PGA, and a power consumption of the circuit is decreased.

Abstract: A capacitance-to-digital converter for an extended range of capacitances includes a reference capacitor and one or more offset capacitors. Electrical charge accumulated in the offset capacitors is used to at least partially cancel the charge accumulated in a sensed capacitance to facilitate matching with a charge accumulated in the reference capacitor. The residual charge is passed to an integrator, the output from which is quantized and used to control switching of the capacitors. Immunity to tonal external noises and improved conversion speed are achieved by controlling the capacitor switching with a spread spectrum clock. The capacitance-to-digital converter may be used, for example, for sensing of the capacitances of capacitive elements in touch and proximity displays or other user interfaces.

Abstract: An A/D converter device is provided, which has a D/A conversion function and changes a resolution of A/D conversion and D/A conversion. The A/D converter device is configured to selectively execute an A/D conversion operation and a D/A conversion operation, by the operation of a control circuit controlling switching of switches according to an ADC/DAC function switching signal supplied from an external side. The A/D conversion operation performs A/D conversion of an input signal voltage inputted via a signal input terminal from an external side and outputs an A/D conversion value of 12 bits. The D/A conversion operation outputs, via a signal output terminal, an analog voltage produced by performing D/A conversion of a digital value supplied from the external side.

Abstract: An analog-to-digital converter (ADC) system configured to receive a first and a second analog quantity and to provide a plurality of numerical parameters representative of the first and second analog quantities. The ADC system includes a first, a second, and a third ADC circuit, and a digital interface circuit. The first ADC circuit is configured to provide a first code representative of the first analog quantity and to provide a first analog residue quantity representative of the first analog quantity with respect to the first code. The second ADC circuit is configured to provide a second code representative of the second analog quantity and to provide a second analog residue quantity representative of the second analog quantity with respect to the second code. The third ADC circuit is configured to receive the first and second analog residue quantities, and to provide a third digital code representative of a difference of the first and second analog residue quantities.

Abstract: In one embodiment, a method for converting an analog input value to a digital output value is disclosed. A successive approximation is performed. The analog input is quantized to a first quantized value, which is converted to a first analog value using a DAC. The first analog value is subtracted from the analog input value to form a first residue. The first residue is quantized to form a second quantized value, and a second residue is formed by converting the second quantized value to a second analog value using the DAC and subtracting the second analog value from the first residue value. The second residue is then quantized to form a third quantized value. The first, second and third quantized values are converted into a digital output value. The first, second and third quantized values each have at least three levels.

Abstract: A sigma-delta modulator has a chopper voltage reference providing a reference signal having a clock dependent offset voltage, a single-bit or a multi-bit digital-to-analog converter (DAC); a plurality of capacitor pairs; a plurality of switches to couple any capacitor pair to an input or reference signal; and a control unit controlling sampling through said switches to perform a charge transfer in two phases wherein any capacitor pair can be selected to be assigned to the input or reference signal, wherein after a plurality of charge transfers a gain error cancellation is performed by rotating the capacitor pairs cyclically, and wherein a DAC output value and a reference offset state define switching sequences wherein each switching sequence independently rotates said capacitor pairs and wherein at least one switching sequence is selected depending on a current DAC output value and a current reference offset state.

Abstract: An integrated circuit allows for the isolation of the input of an analog-to-digital converter (ADC) from a summing-node (SNS) algorithm. The integrated circuit contains a gating device that is controlled by bits of a flash analog-to-digital converter (ADC) to gate input samples to sub-ranges that are used by the SNS algorithm. A single sub-range is chosen to be used by the SNS algorithm.

Abstract: A singled-ended, successive approximation register analog-to-digital converter convert an analog input voltage to a digital representation comprising m upper order bits and a number of lower order bits. The SAR ADC comprises SAR logic, a resistive network, multiple switches, and first and second LSB capacitors. The switches also comprises two sets of switches coupled to the resistive network, each set of switches is configured to couple a selected tap to each of the first and second LSB capacitors. When determining the lower order bits, the SAR logic is configured to control the sets of switches to change the first and second taps from one cycle in which one of the lower order bits is determined to a next cycle in which the next of the lower order bits is determined so that the voltage of both taps changes by a decreasing amount with each succeeding bit being determined.

Abstract: An uncalibrated converter element in an analog-digital converter may be replaced with two or more smaller elements having an effective total net value that is equal to that of the uncalibrated converter element. In an exemplary case where the element is capacitor, one or more of these smaller capacitors may be independently calibrated by switching the smaller capacitor between two voltages, such as a reference voltage and ground, and then calculating a difference of corresponding digital output codes generated by the backend ADC with previously calibrated capacitors associated with lesser significant bits. The total capacitance of the uncalibrated capacitor may be apportioned between the smaller capacitors so that the individual maximum charge contribution of each smaller capacitor to the converter output together with any expected manufacturing variance does not exceed the aggregated contribution of the previously calibrated capacitors.

Abstract: An SAR ADC includes a digital-to-analog converter, a first comparator that compares an input analog signal with a reference analog signal, a second comparator that compares an input analog signal with a reference analog signal, a selection circuit that selects one of comparison results of the first comparator and the second comparator, and a control circuit that changes the multibit digital signal sequentially based on the selected comparison result in a plurality of steps so that the reference analog signal becomes closer to the input analog signal, and the control circuit controls the selection circuit to select the comparison result of the first comparator up to an intermediate step on the way of the plurality of steps and to select the comparison result of the second comparator after the intermediate step, and changes the bit value of the multibit digital signal according to the non-binary algorithm.

Abstract: Methods, systems and other embodiments associated with charging merchandise items are presented. A method of charging merchandise items includes displaying merchandise items at a consumer display so that the merchandise items can be handled by a consumer. A first powers supply charges a portion of the display that does not include the merchandise items and a second power supply charges the merchandise items. The merchandise items are charged at the display on a multiplexed basis. An alarm is generated if the first power supply or the second power supply looses power but not if the first and second power supply loose power.

Abstract: Successive approximation register (SAR) and ramp analog to digital conversion (ADC) methods, systems, and apparatus are disclosed. An analog voltage signal may be converted into a multiple bit digital value by generating bits of the multiple bit digital value by performing a SAR conversion on the analog voltage signal, where the bits corresponding to a SAR voltage level, and generating other bits of the multiple bit digital value by performing one or more ramp conversions on the analog voltage signal, the ramp conversion comparing the analog voltage signal to a ramp of voltage levels based on the SAR voltage level. The SAR and ramp ADC can provide multi-sampling using one SAR conversion and multiple ramp conversions. The SAR can set the voltage level of a first ramp of a multiple ramp conversion, which can then be used to preset the voltage level prior to subsequent ramps.

Abstract: A switched-capacitor circuit (10, 32 or 32A) samples a first signal (VIN+) onto a first capacitor (C1 or CIN1) by switching a top plate thereof via a summing conductor (13) to a first reference voltage (VSS) and switching a bottom plate thereof to the first signal. A second signal (VIN?) is sampled onto a second capacitor (C3 or CIN3) by switching a top plate thereof to the second signal and switching a bottom plate thereof to the first reference voltage. After the sampling, the top plate of the second capacitor is coupled to the top plate of the first capacitor. The bottom plate of the second capacitor is coupled to the first reference voltage.