Methods and systems for an analog-to-digital converter (ADC) with constant common mode voltage may include in an ADC comprising a sampling switch on a first input line to the ADC, a sampling switch on a second input line to the ADC, N switched capacitor pairs and M single switched capacitors on the first input line, and N switched capacitor pairs and M single switched capacitors on the second input line: sampling an input voltage by closing the sampling switches, opening the sampling switches and comparing voltage levels between the input lines, iteratively switching the switched capacitor pairs between a reference voltage (Vref) and ground based on the compared voltage levels, and iteratively switching the single switched capacitors between ground and voltages that are a fraction of Vref, which may equal Vref/2.sup.x where x ranges from 0 to m1 and m is a number of single switched capacitors per input line.

Methods and systems for an analog-to-digital converter (ADC) with constant common mode voltage may include in an ADC comprising a sampling switch on a first input line to the ADC, a sampling switch on a second input line to the ADC, N switched capacitor pairs and M single switched capacitors on the first input line, and N switched capacitor pairs and M single switched capacitors on the second input line: sampling an input voltage by closing the sampling switches, opening the sampling switches and comparing voltage levels between the input lines, iteratively switching the switched capacitor pairs between a reference voltage (Vref) and ground based on the compared voltage levels, and iteratively switching the single switched capacitors between ground and voltages that are a fraction of Vref, which may equal Vref/2.sup.x where x ranges from 0 to m1 and m is a number of single switched capacitors per input line.

A semiconductor device according to an aspect of the invention relates to an AD converter that converts a signal level of an analog signal into a digital value by using a comparator, and determines an amount of adjustment of an offset voltage of the comparator based on an offset determination result of the comparator obtained immediately after a least significant bit (LSB) of a digital value output as a conversion result is converted.

A multiplying analog to digital converter including an analog to digital converter (ADC) having a sample input and a feedback input and an ADC output configured with a feedback path configured to couple the ADC output to a digital to analog converter. A feedback attenuator is disposed in the feedback path, the feedback attenuator being configured to attenuate a feedback signal coupled to the feedback input, the feedback attenuator being configured to provide analog multiplication observed at the ADC output. A barrel shifter is configured to provide digital multiplication of the ADC output. The feedback attenuator may be configured as a divider network. The feedback attenuator may be configured to provide attenuation using only passive components. The feedback attenuator may be configured as a capacitive divider network. The feedback attenuator may be configured to provide attenuation ranging between 1 and 0.5.

In a microelectromechanical system (MEMS) sensor, movement of a component such as a proof mass due to a force of interest is sensed capacitively. A capacitance-to-voltage (C2V) converter receives a capacitance signal from the sensor and outputs a signal that includes an offset in addition to a signal of interest. The output signal is analyzed to identify the offset portion of the output signal and to modify values one or more variable capacitors coupled to the C2V input reduce the offset portion of the output signal.

A method for adaptively regulating a coding mode and a digital correction circuit thereof are provided. The method is for a successive-approximation-register analog-to-digital converter (SAR ADC). In the method, whether to regulate a binary weight corresponding to each of digital bits is determined according to the number of completed comparison cycles to provide a first coding sequence. The first coding sequence is directly compensated according to uncompleted comparison cycles to provide a correct digital output code.

Methods and systems for an analog-to-digital converter (ADC) with constant common mode voltage may include in an ADC comprising a sampling switch on a first input line to the ADC, a sampling switch on a second input line to the ADC, N switched capacitor pairs and M single switched capacitors on the first input line, and N switched capacitor pairs and M single switched capacitors on the second input line: sampling an input voltage by closing the sampling switches, opening the sampling switches and comparing voltage levels between the input lines, iteratively switching the switched capacitor pairs between a reference voltage (Vref) and ground based on the compared voltage levels, and iteratively switching the single switched capacitors between ground and voltages that are a fraction of Vref, which may equal Vref/2.sup.x where x ranges from 0 to m1 and m is a number of single switched capacitors per input line.

Systems comprising: a first MDAC stage comprising: a sub-ADC that outputs a value based on an input signal; at least two reference capacitors that are charged to a Vref; at least two sampling capacitors that are charged to a Vin; and a plurality of switches that couple the at least two reference capacitors so that they are charged during a sampling phase, that couple the at least two sampling capacitors so that they are charged during the sampling phase, that couple at least one of the reference capacitors so that it is parallel to one of the at least two sampling capacitors during a hold phase, and that couple the other of the at least two sampling capacitors so that it couples the at least one of the reference capacitors and the one of the at least two sampling capacitors to a reference capacitor of a second MDAC stage.

A method for adaptively regulating a coding mode and a digital correction circuit thereof are provided. The method is for a successive-approximation-register analog-to-digital converter (SAR ADC). In the method, whether to regulate a binary weight corresponding to each of digital bits is determined according to the number of completed comparison cycles to provide a first coding sequence. The first coding sequence is directly compensated according to uncompleted comparison cycles to provide a correct digital output code.

A semiconductor device according to an aspect of the invention relates to an AD converter that converts a signal level of an analog signal into a digital value by using a comparator, and determines an amount of adjustment of an offset voltage of the comparator based on an offset determination result of the comparator obtained immediately after a least significant bit (LSB) of a digital value output as a conversion result is converted.