A method of washing polycrystalline silicon is provided. Embodiments of the present invention operate in accordance with an intra-vascular ultrasound device and a computing device electrically connected thereto. Software designated an abstraction layer provides communication between the internal virtual phone application program interface, the telephone switch and the telephone set. Compensation for a voltage drop is made by using the compensation signal for an increase in voltage such that the apparent voltage drop due to the output current is limited to a small value.