A 100dB SFDR 0.5V pk-pk band-pass DAC implemented on a low voltage CMOS process

Direct Digital Synthesis (DDS) systems generate fine frequency resolution signals over a broad spectrum that are used in a wide variety of applications such as multi-mode RF, communications, measurements and test. A high performance DDS band-pass Digital to Analog Converter (DAC) architecture and implementation is presented that delivers high spectral purity over a narrow-band response. The low power D/A Converter is portable to standard CMOS processes and designed to achieve over 100dB narrow-band SFDR performance using Sigma-Delta (ΣΔ) modulation and multi-bit current steering techniques. A 3rd order digital ΣΔ modulator is combined with a 4th order digital Dynamic Element Matching (DEM) block to shape the noise while calibrating for process mismatch variations. A low silicon area output stage is used to deliver a high performance specification

Energy autonomous sensor systems: Towards a ubiquitous sensor technology

Energy efficiency of electronic systems has emerged as one of the most important trends in integrated circuits research in recent years. The results of this continued effort are visible in all kinds of electronic functions: DSPs (reaching the 10 W/MMAC according Gene's law), data converters (the FOM of recent ADCs is approaching 15 fJ/conversion step [1] (Liu et al., 2010)), power converters (reaching unprecedented efficiencies in ultra-low-power regime) and radios (achieving an energy budget lower than 1 nJ per received-transmitted bit [2,3] (Daly et al., 2010; Mercier et al., 2008)). Exploiting this continuously improving energy efficiency, the progressing battery technology and advances in energy harvesting, miniaturized electronic sensors that do not need to be recharged for their whole operational life and can communicate among them to build up an energy-autonomous system are possible nowadays. A working group has been set up by CATRENE1 to study the state and the development of these "energy autonomous systems". This paper summarizes the findings of the working group, expanding and updating in this special issue of the Microelectronics Journal on IWASI09 the report written for the proceedings of the workshop [4] (Belleville et al., 2008)