Ultra Low-Power 12-Bit SAR ADC for RFID Applications
The design and first measuring results of an ultra-low power 12bit Successive-Approximation ADC for autonomous multi-sensor systems are presented. The comparator and the DAC are optmised for the lowest power consumption. The proposed design has a power consumption of 0.52?W at a bitclock of 50-kHz and of 0.85?W at 100-kHz with a 1.2-V supply. As far as the authors know, the Figure-of-Merit of 66 fJ/convertion-step is the best reported so far. The ADC was realised in the NXP CMOS 0.14?m technology with an area of 0.35 mm2. Only four metal layers were used in order to allow 3D integration of the sensors.