PHD defense of M.Thomas COULOT

Wireless sensor networks require calculation functions and radiofrequency transmission modules within each sensor. RF SoCs integrating these functions must have the biggest battery life and so a very small consumption. Today, innovative power management systems could highly enhance the energy performances of this type of RF SoC. Indeed, these power systems perform energy conversion and also the isolation functions of RF and digital blocks. Their features are thus estimated in terms of energy efficiency, transient response and also isolation between blocks and noise rejection.
This thesis work concerns the integration of the power management systems and its distribution channels into different ultra-low-power SoCs. This was achieved mainly thanks to the development of a new top-down approach. This new methodology consists of determining the sensibility of every block to its power supply and of designing an innovative and dynamic architecture of power management circuits on the SoC. This study ends up in the implementation of a very efficient low dropout (LDO) regulator for noise-sensitive low-current RF blocks in mixed SoC applications. The fabricated prototype achieves a high power supply rejection for a wide range of frequencies.

Keywords:
wireless sensor network, radiofrequency, power supply strategy, ultra-low-power, transceiver, modeling, Verilog-A, MOS transistor, 90nm CMOS, low dropout regulator, multi-loops, high PSR.