Abstract: A plasma processing apparatus may include a mechanism for generating a plasma, a processing platform for supporting a substrate to be processed, and a voltage waveform generator having an output electrically coupled to the processing platform. The voltage waveform generator includes a plurality of first buck converters arranged in parallel and coupled to the output. The first buck converters include actively switchable semiconductor switches. A control unit is configured to operate the actively switchable semiconductor switches through pulse width modulation signals, and the control unit is configured to operate the plurality of first buck converters in an interleaved manner.

Abstract: Methods and devices for generating a voltage waveform at an output may include providing four DC voltages of different magnitudes. The first (V1) magnitude is higher than the third (V3) and fourth (V4) magnitude. The fourth DC voltage is coupled to the output followed by coupling the first DC voltage to the output, to bring an output voltage (VP) at the output to a high level. The first DC voltage is decoupled from the output, followed by coupling the third DC voltage to the output, to obtain a drop of the output voltage (VP). A ground potential (V0) is coupled to the output following coupling the third DC voltage and the second DC current (I2) is coupled to the output following coupling the ground potential, wherein the second DC current ramps down the output voltage (VP).

Abstract: Methods and devices for generating a voltage waveform at an output may include providing four DC voltages of different magnitudes. The first (V1) magnitude is higher than the third (V3) and fourth (V4) magnitude. The fourth DC voltage is coupled to the output followed by coupling the first DC voltage to the output, to bring an output voltage (VP) at the output to a high level. The first DC voltage is decoupled from the output, followed by coupling the third DC voltage to the output, to obtain a drop of the output voltage (VP). A ground potential (V0) is coupled to the output following coupling the third DC voltage and the second DC current (I2) is coupled to the output following coupling the ground potential, wherein the second DC current ramps down the output voltage (VP).

Abstract: A plasma processing apparatus may include a mechanism for generating a plasma, a processing platform for supporting a substrate to be processed, and a voltage waveform generator having an output electrically coupled to the processing platform. The voltage waveform generator includes a plurality of first buck converters arranged in parallel and coupled to the output. The first buck converters include actively switchable semiconductor switches. A control unit is configured to operate the actively switchable semiconductor switches through pulse width modulation signals, and the control unit is configured to operate the plurality of first buck converters in an interleaved manner.

Abstract: The present specification relates to an electric power converter, comprising at least a set of four controllable power switches, arranged in an H-bridge or a functionally equivalent circuit comprising two switching legs of two series switches connected to a voltage source, each power switch comprising an antiparallel diode, a controller configured for controlling the switches with a blanking time, a feedback loop for the load current, characterized by a first bias current injection circuit, coupled to the central point of the first leg of the H-bridge and a second bias current injection circuit, coupled to the central point of the second leg of the H-bridge. The specification further relates to a MRI scanner, provided with an electric power converter according to any of the preceding claims, for driving the gradient coils.

Abstract: The present specification relates to an electric power converter, comprising at least a set of four controllable power switches, arranged in an H-bridge or a functionally equivalent circuit comprising two switching legs of two series switches connected to a voltage source, each power switch comprising an antiparallel diode, a controller configured for controlling the switches with a blanking time, a feedback loop for the load current, characterised by a first bias current injection circuit, coupled to the central point of the first leg of the H-bridge and a second bias current injection circuit, coupled to the central point of the second leg of the H-bridge. The specification further relates to a MRI scanner, provided with an electric power converter according to any of the preceding claims, for driving the gradient coils.

Abstract: A switched power converter unit has a DC voltage source with a positive output connection and a negative output connection; a series connection of two switching units; a first output clamp, coupled to a common point of the two switching units of a first parallel branch via a first inductive element; a diode arranged to allow current flow from the first output clamp to the DC voltage source; a diode arranged to allow current flow from the DC voltage source to the first output clamp; a capacitor coupled parallel to diode D1, and/or a capacitor coupled parallel to diode D2; a second output clamp, coupled to a common point of the two switching units of a second parallel branch via a second inductive element; a diode arranged to allow current flow from the second output clamp to the DC voltage source; a diode arranged to allow current flow from the DC voltage source to the second output clamp; a capacitor coupled parallel to diode D3, and/or a capacitor coupled parallel to diode D4.

Abstract: A switched power converter unit has a DC voltage source with a positive output connection and a negative output connection; a series connection of two switching units; a first output clamp, coupled to a common point of the two switching units of a first parallel branch via a first inductive element; a diode arranged to allow current flow from the first output clamp to the DC voltage source; a diode arranged to allow current flow from the DC voltage source to the first output clamp; a capacitor coupled parallel to diode D1, and/or a capacitor coupled parallel to diode D2; a second output clamp, coupled to a common point of the two switching units of a second parallel branch via a second inductive element; a diode arranged to allow current flow from the second output clamp to the DC voltage source; a diode arranged to allow current flow from the DC voltage source to the second output clamp; a capacitor coupled parallel to diode D3, and/or a capacitor coupled parallel to diode D4.