A low power programmable dual-slope ADC for single-chip RFID sensor nodes

An 8-bit, 15 kS/s programmable dual-slope (DS) Analog to Digital Converter (ADC) used in a single-chip RFID sensor nodes is presented. The ADC can be programmed to turn on and off by the RFID control unit to save power by almost 50%. Fabricated in 130 nm CMOS process, it occupies a small area of 0.06 mm
²
. ADC characterization is done on a stand-alone ADC that is always active, and consumes a low dynamic power of 44 µW. The measured differential non-linearity (DNL) is within +/− 0.6 LSB, effective number of bits (ENOB) is 7 bit.