Patent ID: 7710745
Filing Date: 2010-05-04
Classification: B41J,H02M

Abstract:
1. A bipolar power supply system comprising: a control circuit; a negative power supply structured to provide an output current of negative polarity and electrically connected to said control circuit; and a positive power supply structured to provide an output current of positive polarity and electrically connected to said control circuit, wherein said negative and positive power supplies are connected in series, wherein said control circuit provides a transition between said negative and positive power supplies that maintains only one of said negative and positive power supplies in an active state at a time and that causes said bipolar power supply system to provide an output current of only one of said negative and said positive polarity, and wherein said transition between said negative and positive power supplies is caused by a programming voltage input provided by said control circuit to each of said negative and positive power supplies; wherein said programming voltage input provided by said control circuit is created by an operational amplifier situated in said control circuit, said operational amplifier receiving a current feedback from said negative and positive power supplies; wherein said programming voltage is provided to an error operational amplifier situated in each of said negative and positive power supplies, wherein there is no output current from said bipolar power supply system when said programming voltage is a reference voltage, wherein said positive power supply is in an active state when said programming voltage is higher than said reference voltage, and wherein said negative power supply is in active state when said programming voltage is below said reference voltage; and further wherein said programming voltage is applied to the inverting input of said error operational amplifier, and wherein said error operational amplifier adjusts its output to develop an error voltage input to the non-inverting input of said error operational amplifier, thereby creating a system balance and a regulation of said output current for that one of said negative and positive power supplies that is in an active state; wherein said control circuit provides a transition between said negative and positive power supplies at a speed of less than ten milliseconds.