Eric Vittoz - IEEE

TECHNICAL LITERATURE
be extended to the design of low-power and lowvoltage
RF-CMOS circuits. This work was then continued
at the CSEM, migrating the original design to a
0.18 μm standard digital process and including all the
functions required by a wireless sensor node (sensor
interface, ADC, μC, embedded low-leakage SRAM,
power management, etc) on a complex system-onchip
(SoC) [74]. This set the basis for new RF-CMOS
activity at CSEM that started in 2001 and focuses on
the design of ultra low-power radios for wireless sensor
networks [75]. This constitutes a very good example
illustrating the technology transfer mission of
CSEM: Ideas are first explored in the academic environment
(for example at EPFL) and if successful they
are transferred to CSEM for further improvement and
consolidation before being proposed to industry as a
technology platform that can be customized and
industrialized for a particular application. More recently,
this activity has been combined at CSEM with the
development high-Q resonators such as bulk acoustic
wave (BAW) resonators and temperature-compensated
low-frequency MEMS resonators for the implementation
of an ultra low-power MEMS-based radio [76]-[79].
IV. CONCLUSION
From its beginning, the EKV MOS transistor model really
enabled the design and optimization of new lowpower
and low-voltage analog and RF circuits where
most transistors were operating in the weak and moderate
inversion regions. Together with the development
of the EKV compact model, a design methodology for
low-power circuits based on the inversion factor was
formulated. This powerful concept allows the optimum
operating point to be chosen and the transistor to be
sized accordingly. The availability of a MOS transistor
model and the related design methodology that is valid
in all modes of operation becomes even more crucial
today. Indeed, with the aggressive downscaling of
CMOS technologies, the operating points of analog and
even RF circuits transistors are more and more shifted
from the traditional strong inversion region towards the
moderate and eventually the weak inversion regions.
ACKNOWLEDGMENT
First I would like to thank Prof. Eric Vittoz who taught
me the art and science of low-power CMOS analog IC
design based on a deep understanding of the operation
and correct modeling of the MOS transistor. I would
also like to thank all my Ph.D. students who pushed
the limit of low-power IC design always a bit further.
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28 IEEE SSCS NEWS Summer 2008