Bias supply with resonant switching

A bias supply to apply a periodic voltage comprising:

• an output node;
• a return node;
• a power section coupled to the output node and the return node;
• a resonant switch section coupled to the power section at a first node, a second node, and a third node wherein the resonant switch section is configured to connect and disconnect a current pathway between the first node and the second node to cause an application of an asymmetric periodic voltage waveform at the output node relative to the return node, wherein each cycle of the asymmetric periodic voltage waveform includes a first portion that begins with a first negative voltage and changes to a positive peak voltage, a second portion that changes from the positive peak voltage level to a third voltage level and a fourth portion that includes a negative voltage ramp from the third voltage level to a fourth voltage level;
• and
• an offset voltage source, wherein a second node of a secondary winding of the transformer is coupled to the return node via the offset voltage source;
• wherein the power section comprises:
• a transformer, a first node of a primary winding of the transformer coupled to a second node of the resonant switch section, a first node of the secondary winding of the transformer coupled to the output node, and a second node of the secondary winding of the transformer coupled to the return node;
• and
• a voltage source coupled between a second node of the primary winding of the transformer and the return node.