This disclosure describes systems, methods, and apparatus for operating a plasma processing chamber. In particular, a periodic voltage function combined with an ion current compensation can be provided as a bias to a substrate support as a modified periodic voltage function. This in turn effects a DC bias on the surface of the substrate that controls an ion energy of ions incident on a surface of the substrate. A peak-to-peak voltage of the periodic voltage function can control the ion energy, while the ion current compensation can control a width of an ion energy distribution function of the ions. Measuring the modified periodic voltage function can provide a means to calculate an ion current in the plasma and a sheath capacitance of the plasma sheath. The ion energy distribution function can be tailored and multiple ion energy peaks can be generated, both via control of the modified periodic voltage function.