The dual supply voltage (dual-VDD) scheme reduces the active power consumption without performance degradation by using two power supply rails. However, an increase in the delay due to the scaled-down supply voltage has made assigning the lower supply voltage (VDDL) more difficult in the conventional dual-VDD scheme. We propose a technique for the dual-VDD scheme employing the Active Body-biasing Control (ABC) on PD-SOI, which increases the number of VDDL-cells owing to lowered threshold voltage. Simulation results have shown our approach effectively reduces the power consumption even at low voltage operation.
A dual-clock MASH (multi-stage noise shaping) delta-sigma modulator (DSM) is proposed for high performance analog-digital converter. This employs a DSM using a frequency modulated intermediate signal (FMDSM) for the last stage. The sampling clock frequency for the last stage can be increased due to the features of the FMDSM. It is shown that this can increase the SNR beyond the conventional MASH DSMs.