POWER SUPPLY DEVICE FEATURING SYNCHRONOUS MODE AND ASYNCHRONOUS MODE OPERATION

摘要

A POWER SUPPLY DEVICE FEATURING BOTH SYNCHRONOUS MODE AND ASYNCHRONOUS MODE OPERATION IS PROVIDED. THE POWER SUPPLY INCLUDES A DC POWER SUPPLY, A SWITCHING UNIT, A TRANSFORMER, A POWER CONTROL UNIT, A FREQUENCY MODULATION UNIT, A SYNCHRONOUS SELECTION UNIT. THE SWITCHING UNIT, RECEIVING A FIRST PULSE SIGNAL TO EXECUTE AN ON/OFF OPERATION WHOSE FREQUENCY IS SYNCHRONOUS WITH THAT OF THE FIRST PULSE SIGNAL. THE TRANSFORMER AT LEAST COMPRISES A PRIMARY WINDING AND A SECONDARY WINDING, WHEREIN THE DC POWER SUPPLY IS APPLIED AT THE PRIMARY WINDING AND THE SWITCHING UNIT TO PRODUCE OUTPUT VOLTAGE AT THE SECONDARY WINDING. THE POWER CONTROL UNIT, OUTPUTTING THE FIRST PULSE SIGNAL TO CONTROL THE OUTPUT VOLTAGE AT THE SECONDARY WINDING. THE FREQUENCY MODULATION UNIT IS COUPLED TO A FREQUENCY-MODULATION TERMINAL OF THE POWER CONTROL UNIT. THE SYNCHRONOUS SELECTION UNIT, RECEIVING A SECOND PULSE AND A SYNCHRONOUS SELECTION SIGNAL, HAS AN OUTPUT TERMINAL COUPLED TO THE FREQUENCY MODULATION UNIT. WHEN THE SYNCHRONOUS SIGNAL IS ENABLED, THE SECOND PULSE SIGNAL IS DIFFERENTIATED BY THE SYNCHRONOUS SELECTION UNIT FOR OUTPUTTING TO THE FREQUENCY MODULATION UNIT AND SYNCHRONOUS WITH THE FIRST PULSE SIGNAL, AND WHEN THE SELECTION SYNCHRONOUS IS DISABLED, THE SYNCHRONOUS SELECTION UNIT DOES NOT DIFFERENTIATE THE SECOND PULSE SIGNAL, AND THE FREQUENCY OF THE FIRST PULSE SIGNAL IS DETERMINED BY THE FREQUENCY MODULATION UNIT.