Signal boosting to extend the bandwidth of oversampled converters

This paper presents a novel technique to extend the bandwidth of oversampled Analog-to-Digital Converters and a method to optimize their design to avoid instability, when oversampling has to be preserved and clock frequency cannot be increased. This proposal allows the converter to increase the resolution only introducing minor circuit modifications when processing input signals in the extended band or even in both bands concurrently is needed for different applications. The technique consists of boosting the signal in the extended band by modifying the signal transfer function of the converter and keeping the noise transfer function unaffected. An improvement of 6dB in the Signal-to-Noise Ratio is reached, which allows to maintain the order of the loop filter or the resolution of the quantizer, thus saving power consumption and silicon area.