An RF acceleration system, in which digital control with a direct digital s
ynthesizer (DDS) is applied, has been developed for the Heavy Ion Medical A
ccelerator in Chiba (HIMAC) synchrotron. This digital system allows us to o
btain stable operation of the acceleration system over a wide frequency ran
ge from 1.04 to 7.9 MHz. In this paper the designed digital RF control syst
em and its performance are described. (C) 2000 Elsevier Science B.V. All ri
ghts reserved.