Patent ID: 6666960
Filing Date: 2003-12-23
Classification: C25D,H02J,H05K

Abstract:
An electroplating current supply system comprising:a power supply unit including a first DC power supply apparatus supplying a positive current and a second DC power supply apparatus supplying a negative current, for supplying a plating load with an electroplating current the polarity of which is inverted at predetermined intervals; and a processing unit for controlling the ratio of a positive current value of said electroplating current supplied to said plating load from said first DC power supply apparatus to a negative current value of said electroplating current supplied to said plating load from said second DC power supply apparatus, and the ratio of a period during which said positive current is supplied to said plating load to a period during which said negative current is supplied to said plating load; wherein: said first DC power supply apparatus includes a first DC power supply and a first main switching device coupled between one output of said first DC power supply and one load terminal adapted to be coupled to said plating load, said first main switching device being turned on and off in response to a first control signal provided thereto from said processing unit, the other output of said first DC power supply being connected to the other load terminal adapted to be coupled to said plating load; said second DC power supply apparatus includes a second DC power supply and a second main switching device coupled between one output of said second DC power supply and said other load terminal, said second main switching device being turned on and off in response to a second control signal provided thereto from said processing unit, the other output of said second DC power supply being coupled to said one load terminal; and said processing unit provides said first and second control signals in such a manner that said first and second main switching devices can be turned on alternatively.