In some examples, a system comprises an analog-to-digital converter (ADC) to receive an analog input signal and a reset signal, the ADC to convert the analog input signal into a digital signal. The system comprises a digital-to-analog converter (DAC), coupled to the ADC, to convert the digital signal into an internal analog signal. The system includes a first capacitor, coupled to the DAC, to receive the internal analog signal. The system comprises a first switch, coupled to the first capacitor, to provide the analog input signal to the first capacitor. The system comprises a second switch to couple the first capacitor to ground.

In some examples, a system comprises an analog-to-digital converter (ADC) to receive an analog input signal and a reset signal, the ADC to convert the analog input signal into a digital signal. The system comprises a digital-to-analog converter (DAC), coupled to the ADC, to convert the digital signal into an internal analog signal. The system includes a first capacitor, coupled to the DAC, to receive the internal analog signal. The system comprises a first switch, coupled to the first capacitor, to provide the analog input signal to the first capacitor. The system comprises a second switch to couple the first capacitor to ground.

Aspects of the disclosure are directed to compensating for errors in in an analog-to-digital converter circuit (ADC). As may be implemented in accordance with one or more embodiments, an apparatus and/or method involves an ADC that converts an analog signal into a digital signal using an output from a digital-to-analog converter circuit (DAC). A compensation circuit generates a compensation output by, for respective signal portions provided to the DAC, generating a feedback signal based on an incompatibility between the conversion of the signal portions into an analog signal and the value of the signal portions provided to the DAC. A compensation output is generated based on the signal input to the DAC with a gain applied thereto, based on the feedback signal. Hereby, the digital inputs provided to the DACs are non-randomized.

Methods and apparatuses are described to convert analog signals to digital signals using a local charge averaging capacitor array (LCACA) in an analog-to-digital converter (ADC.) An apparatus includes a comparator. The comparator is configured with a first high input, a first low input, and is configure to receive a clock signal. A logic/latch block is configured to receive the clock signal and an output from the comparator. The logic/latch block is configured to output a control signal and a digital N-bit output signal. A local charge-averaging capacitor array (LCACA) is configured to receive the control signal and a reference voltage. An output of the LCACA is coupled to the first low input. The first LCACA is divided into a high sub-array and a low sub-array. The high sub-array is pre-charged to a high reference voltage and the low sub-array is pre-charged to a low reference voltage. The high reference voltage is greater than the low reference voltage. In operation, an analog signal is input to the first high input and the digital N-bit output signal is the digital conversion of the analog signal.