  Sirius is a Synchrotron Light Source Facility based on a 4th generation low
emittance storage ring. The facility is presently in the final assembly phase
in Campinas, Brazil, and comprises a 3 GeV electron storage ring, a full energy
Booster and a 150 MeV Linac. The Booster RF system is based on a single 5-cell
RF cavity driven by a 45 kW amplifier at 500 MHz and is designed to operate at
2 Hz repetition rate. The storage ring will initially use one normal conducting
7-cell RF cavity and, in the final configuration, will comprise two
superconducting cavities, each one driven by a 240 kW RF amplifier. A digital
LLRF system based on ALBA DLLRF has been designed and commissioned to control
both normal conducting and future superconducting RF configurations. The first
DLLRF system is already in operation in the injector Booster. This paper
presents an overview of the performance of the control loops in high power
operation and the results of the Booster DLLRF commissioning. It also shows the
integration of DLLRF with the RF system as well as other utilities of the
system such as automatic start-up, conditioning, fast interlocks and
post-mortem analysis.
