Various embodiments of the present technology may provide methods and apparatus for a successive approximation register analog-to-digital converter (SAR ADC). The SAR ADC may provide a first digital calibration circuit configured to correct systemic mismatch and a second digital calibration circuit configured to correct random mismatch. Together, the first and second digital calibration circuits resolve missing codes in the SAR ADC output.

Methods and apparatus for determining non-linearity in analog-to-digital converters are disclosed. An example apparatus includes a signal interface to receive an output of an analog-to-digital converter (ADC), the output corresponding to a periodic signal transmitted to the ADC; a signal transformer to determine at least one of a harmonic phase or a harmonic amplitude corresponding to the output; and an integral non-linearity (INL) term calculator to determine the INL of the ADC based on a characteristic of the periodic signal and the at least one of the harmonic phase or the harmonic amplitude.

The present disclosure relates to the field of semiconductor integrated circuits, and to a method for calibrating a capacitor voltage coefficient of a high-precision successive approximation analog-to-digital converter (SAR ADC). The method includes: calibrating a voltage coefficient; obtaining a sampled charged charge according to a capacitance model with the voltage coefficient; according to an INL value obtained by testing, first verifying whether a maximum value of INL occurs in the place shown in Equation 3, then obtaining two very close second-order capacitor voltage coefficients according to Equation 4, and taking an average value thereof as a second-order capacitor voltage coefficient; and then calibrating the second-order capacitor voltage coefficient in a digital domain. In the present disclosure, a capacitor voltage coefficient can be extracted based on INL and the capacitor voltage coefficient is calibrated at a digital backend without adding an analog calibration circuit, thereby improving conversion accuracy of the ADC.

Techniques are described that can be used to extract an offset and a gain of a signal chain, which can be used for digital correction of an analog-to-digital converter (ADC) output to help achieve a life time and temperature stable ADC output. For example, using various techniques, a value for a voltage reference VREF and a value for ground (GND) (or other reference voltage) can be converted, which can then be used to determine gain and offset, respectively, of the signal chain.

VCO ADCs consume relatively little power and require less area than other ADC architectures. However, when a VCO ADC is implemented by itself, the VCO ADC can have limited bandwidth and performance. To address these issues, the VCO ADC is implemented as a back end stage in a VCO-based continuous-time (CT) pipelined ADC, where the VCO-based CT pipelined ADC has a CT residue generation front end. Optionally, the VCO ADC back end has phase interpolation to improve its bandwidth. The pipelined architecture dramatically improves the performance of the VCO ADC back end, and the overall VCO-based CT pipelined ADC is simpler than a traditional continuous-time pipelined ADC.

An IC can include shared reference voltage buffer circuitry having an amplifier circuit. A commonly-routed amplifier shared output voltage node can be shared between at least two digital-to-analog converters (DACs) respectively via at least first and second individually routed traces from the shared output voltage node to respective first and second local reference voltage nodes at the DACs. Respective first and second routing trace resistances can be based on current draw of the corresponding DAC, such as to provide an equal voltage drop across the first and second routing resistances. This can help avoid voltage contention or conflict at the shared output voltage node from forcing/sensing the voltages at the first and second local reference voltage nodes. In a further example, at least one of the first and second individually routed traces can include a binary tree hierarchical routing arrangement of at least some of the DACs.

Non-idealities of input circuitry of a receiver signal chain can significantly degrade the overall performance of the receiver signal chain. To meet high performance requirements, the input circuitry is typically implemented with power hungry circuitry in a different semiconductor technology from the analog-to-digital converter that the input circuitry is driving. With suitable optimization techniques, performance requirements on the input circuitry can be reduced while meeting target performance of the receiver signal chain. Specifically, optimization techniques can compensate for input frequency-dependent properties and/or amplitude-dependent properties of the input circuitry. In some cases, reducing performance requirements on the input circuitry means that the input circuitry can be implemented in the same semiconductor technology as the analog-to-digital converter.

Various embodiments of the present technology may provide methods and apparatus for a successive approximation register analog-to-digital converter (SAR ADC). The SAR ADC may provide a first digital calibration circuit configured to correct systemic mismatch and a second digital calibration circuit configured to correct random mismatch. Together, the first and second digital calibration circuits resolve missing codes in the SAR ADC output.

Non-idealities of input circuitry of a receiver signal chain can significantly degrade the overall performance of the receiver signal chain. To meet high performance requirements, the input circuitry is typically implemented with power hungry circuitry in a different semiconductor technology from the analog-to-digital converter that the input circuitry is driving. With suitable optimization techniques, performance requirements on the input circuitry can be reduced while meeting target performance of the receiver signal chain. Specifically, optimization techniques can compensate for input frequency-dependent properties and/or amplitude-dependent properties of the input circuitry. In some cases, reducing performance requirements on the input circuitry means that the input circuitry can be implemented in the same semiconductor technology as the analog-to-digital converter.

Techniques are described that can be used to extract an offset and a gain of a signal chain, which can be used for digital correction of an analog-to-digital converter (ADC) output to help achieve a life time and temperature stable ADC output. For example, using various techniques, a value for a voltage reference VREF and a value for ground (GND) (or other reference voltage) can be converted, which can then be used to determine gain and offset, respectively, of the signal chain.