Analog-to-digital converter

Abstract

A continuous-time ΔΣ-ADC () is disclosed, comprising a sampled quantizer () arranged to generate samples y(n) of a digital output signal of the ΔΣ-ADC () at sample instants nT. The ΔΣ-ADC () further comprises two or more DACs (-), each arranged to generate an analog feedback signal based on the samples of the digital output signal generated by the sampled quantizer (), and a continuous-time analog network () arranged to generate an analog input signal to the quantizer () based on the feedback signal(s) from the two or more DACs (-) and an analog input signal to the ΔΣ-ADC (). At least a first DAC () of the two or more DACs (-) is adapted to generate a pulsed feedback signal that, for each n, comprises a pulse, the magnitude of which is proportional to the sample of the digital output signal at sample instant nT and which lasts between the time instants (n+a1)T and (η+β1)T, wherein 0<α1<β1<1. Aí least a second DAC () of the two or more DACs (-) is adapted to generate a pulsed feedback signal that, for each n, comprises a pulse, the magnitude of which is proportional to the sample of the digital output signal at sample instant nT and which lasts between the time instants (n+a2)T and (η+β2)T, wherein 0<a2<1<β2. The first DAC () is located in a first feedback loop and the second DAC () is located in a second feedback loop, which is an outer feedback loop relative to the first feedback loop. A corresponding radio receiver circuit, a corresponding integrated circuit, and a corresponding radio communication apparatus are also disclosed.