An analog-to-digital converter (ADC) and a method are disclosed. The ADC has a quantizer. The quantizer comprises a linear-feedback shift register (LFSR), a decoder configured to provide a plurality of switch control signals at a plurality of decoder outputs, respectively, the plurality of switch control signals responsive to a LFSR value of the LFSR output; an electrical reference, the electrical reference having a plurality of reference outputs, the electrical reference configured to provide a plurality of reference levels at the plurality of reference outputs, respectively; a first switch providing a first switch output and a second switch output; and a comparator, the comparator having a signal input, a first reference input, and a second reference input, the first reference input connected to the first switch output, and the second reference input connected to the second switch output.