Patent ID: 7916506

Claim:
A control device adapted for use in a resonant direct current/direct current converter for controlling a switch unit of the resonant direct current/direct current converter, said control device comprising: a frequency modulation controller adapted to be coupled electrically to the resonant direct current/direct current converter for receiving a correcting threshold value and output information of the resonant direct current/direct current converter, and for generating a synchronization signal according to the correcting threshold value and the output information received thereby; and a pulse selector adapted to be coupled electrically to the resonant direct current/direct current converter and said frequency modulation controller for receiving the output information, the correcting threshold value and the synchronization signal, and for generating a driving signal according to the output information, the correcting threshold value and the synchronization signal received thereby; wherein the driving signal is adapted to drive the switch unit of the resonant direct current/direct current converter, and has a working period, the driving signal switching between high and low signal levels at a frequency that is substantially equal to that of the synchronization signal during the working period.