Abstract: A voltage waveform generator includes a common node, a voltage waveform generation circuit and a current source. The voltage waveform generation circuit is operably connected to the common node and is configured to apply a voltage signal at the common node. The current source is operably connected to the common node and configured to apply a DC current at the common node. The current source has a first switch node connected to the common node through a first inductor, and a first power supply connected to the first switch node. The power supply includes at least two first voltage nodes, and the current source is operable to switch between the at least two first voltage nodes at the first switch node.

Abstract: A voltage waveform generator for a plasma assisted processing apparatus includes a common node, a voltage supply circuit operable to switch between at least two voltage levels at a first switch node, a first inductor connected between the first switch node and the common node, and a control unit configured to operate the voltage supply circuit.

Abstract: An AC-DC converter includes three phase terminals, first and second DC terminals, a first converter stage for converting between the AC signal and a first signal at first and second intermediate nodes, a second converter stage to convert between a second signal at third and fourth intermediate nodes and the DC signal at the first and second DC terminals. The second converter stage has a first active switch. A link connects the first and third intermediate nodes and the second and fourth intermediate nodes. A current injection circuit has second active switches. In a first mode, the first active switch and the second active switches are operated through PWM. In a second mode, the third and fourth intermediate nodes are continuously connected to the first and second DC terminals such that the second converter stage is inoperative and the second active switches are operated through PWM.

Abstract: An electrical converter includes first and second converter stages, an output filter, and a controller having a first mode for converting a three-phase AC signal into a DC signal. The first converter stage has a three-phase bridge rectifier connecting three phase terminals to an upper intermediate node and a lower intermediate node, and a phase selector having first switches connecting the terminals to a middle intermediate node. The second converter stage includes a switch node connected to the middle intermediate node and a pair of second switches connecting the switch node to one of the DC terminals. In a second mode, the first switches are operated while keeping the upper or lower intermediate node disconnected from all the phase terminals to allow a current to flow between the middle intermediate node and the output filter, allowing for stepwise increasing a voltage across the DC terminals during start-up.