Sammendrag
In the continuing hunt for better and more powerful monitoring and control, we
see an increased interest for small and light electronic devices adapted for these
tasks. This is seen both in tracking of goods, machinery, production and other
parts of the industry as well as inside the human body. And every day, new
areas of use are showing up. Following the IT-age is the enormous amount of
information available. Common and revolutionizing for the devices now
developed are their ability to deliver the exact information needed from an exact
location.
This master thesis discusses the different areas regarding development of a
passive (without battery or any device of internal power source) medical implant
from an electronic point of view. The introduction shortly presents the medical
aspects of the diabetes disease and the reasons for this thesis. An overview of
the wireless power transfer used in an inductive link application is given for
understanding the physical aspects, environment and demands present for
passive implants. This leads to identification of two parts that are essential in
any kind of such a passive device, unrelated to the specific task of the implant:
A rectifier to recover a DC-voltage from the AC-input signal, and a regulator for
providing a stable VDD to the whole implant and its circuitry. These two circuits
are fully presented in the last chapters and some different circuit solutions are
presented. These solutions are developed for optimal adaption to the inductive
link and other important parameters regarding this area. The circuit solutions are
presented and produced in the STM CMOS 90nm ASIC1 process, and the
simulated and measured results are investigated and compared.
1 Application