A method of tuning a production module using a reference module with virtual gain correction is provided. The method includes selecting a counterpart reference module created for a select application. The production module is commutatively coupled to the selected counterpart reference module to generate a production module pair. A production module gain curve for the production module pair is measured for each frequency band to be used by the production module. The production module is tuned based at least in part on offset gain values at select number of frequency observation points for each frequency band associated with the counterpart reference module and gain values at the select number of frequency observation points of the measured production module gain curve for each frequency band.

A method for precise acquisition of a signal of a sensor, by an evaluation and control unit which has a multiplexer at whose inputs there is at least one reference voltage whose voltage value is known, a ground potential of the reference voltage, a measurement signal of the exhaust gas sensor, and a ground potential of the measurement signal. A computer is connected downstream from the multiplexer via a transmission path and via an ADC that converts a voltage between its two inputs into a digital value. The method provides that a plurality of individual measurements are carried out in which switching states of the multiplexer are modified, and digital values are subsequently acquired at the output of the ADC. The computer calculates a measurement value, corrected with regard to offset and gain, from these digital values.

A self-calibrating digital-to-analog converter (DAC) is disclosed. The self-calibrating DAC includes an input port, a non-binary DAC, an ADC to receive an output of the non-binary DAC, a lookup table to store a plurality of calibration code and a calibration logic coupled with the non-binary DAC. The self-calibrating DAC has two modes of operations, a calibration mode and a normal operational mode. In the calibration mode, the self-calibrating DAC is configured to calculate weightages of the non-binary DAC and to calculate an offset coefficient and a gain coefficients using high precision on chip analog-to-digital converter (ADC).

A reference buffer has many legs each with an upper transistor, a lower transistor, and a resistor or current source as a tail device in series. The source or emitter of the upper (lower) transistor generates an upper (lower) reference voltage. This source follower transistor configuration has a low output impedance and high current. The gate or base of the upper (lower) transistors are driven by a first (second) control node. A control leg has an upper transistor, a lower transistor, and a tail device in series. The source and gate, or emitter and base, are connected together for the upper and lower transistors and generate the upper and lower control nodes. Alternately, the gate or base of the upper (lower) transistor is driven by an op amp receiving an upper (lower) bandgap voltage and the upper (lower) control node as negative feedback.

According to one embodiment, a semiconductor integrated circuit includes a first converter, a second converter, and an adjustment circuit. The first converter is configured to sample an analog signal and convert the sampled analog signal to a first digital value based on a first clock signal. The second converter is configured to sample the analog signal and convert the sampled analog signal to a second digital value based on a second clock signal shifted a first phase from the first clock signal. The adjustment circuit is configured to adjust at least one of a gain of each of the first digital value and the second digital value and a phase of each of the first clock signal and the second clock signal based on the first digital value and the second digital value.

An analog-to-digital converter includes: a voltage-current converter receiving an analog input voltage, generating a first digital signal from the analog input voltage, and outputting a residual current remaining after the first digital signal; a current-time converter converting the residual current into a current time in a time domain; and a time-digital converter receiving the residual time, and generating a second digital signal from the residual time, wherein the first digital signal and the second digital signal are sequences of digital codes representing respective signal levels of the analog input voltage.

A signal converting apparatus includes a comparing device, a first digital-slope quantizer, and a second digital-slope quantizer. The comparing device having a first input terminal and a second input terminal for receiving a first received signal and a second received signal, and for generating an output signal at an output port. The first digital-slope quantizer generates a first set of digital signals to monotonically adjust the first received signal and the second received signal at the first input terminal and the second input terminal during a first phase according to a first quantization unit. The second digital-slope quantizer generates a second set of digital signals to monotonically adjust the first received signal and the second received signal at the first input terminal and the second input terminal during a second phase after the first phase according to a second quantization unit.

A signal converting apparatus includes a comparing device, a first digital-slope quantizer, and a second digital-slope quantizer. The comparing device has a first input terminal and a second input terminal for receiving a received signal and an adjustable reference voltage respectively, and for generating an output signal at an output port. The first digital-slope quantizer is coupled to the output port and the second input terminal for generating a first set of digital signals to monotonically adjust the adjustable reference voltage at the second input terminal during a first phase according to a first quantization unit. The second digital-slope quantizer is coupled to the output port and the second input terminal for generating a second set of digital signals to monotonically adjust the adjustable reference voltage at the second input terminal during a second phase after the first phase according to a second quantization unit.

Disclosed herein are related to systems and methods for a successive approximation analog to digital converter (SAR ADC). In one aspect, the SAR ADC includes a calibration circuit configured to receive some or all of the plurality of bits corresponding to the input voltage and accumulates or averages at least some of the bits corresponding to the input voltage. The calibration circuit is configured to provide a first offset signal to control a first offset associated with a first comparator, a second offset signal to control a second offset associated with a second comparator, or reduce an offset difference associated with the first offset and the second offset.

A reference buffer has many legs each with an upper transistor, a lower transistor, and a resistor or current source as a tail device in series. The source or emitter of the upper (lower) transistor generates an upper (lower) reference voltage. This source follower transistor configuration has a low output impedance and high current. The gate or base of the upper (lower) transistors are driven by a first (second) control node. A control leg has an upper transistor, a lower transistor, and a tail device in series. The source and gate, or emitter and base, are connected together for the upper and lower transistors and generate the upper and lower control nodes. Alternately, the gate or base of the upper (lower) transistor is driven by an op amp receiving an upper (lower) bandgap voltage and the upper (lower) control node as negative feedback.