A display driver IC for controlling display of an image on a display panel is provided with a memory and a switch circuit. A data connection between an inputoutput device and the image data memory is established and the available series are determined. A series of pulleys is provided which are moveable by rotation of a threaded rod, in order to cause the moveable section of the ladder to extend or retract. When in the expanded position, the emboli capturing device forms a basket with a proximally opening mouth. The number of conversion iterations required to reduce the initial input voltage to below the reference voltage is counted as representing the difference, with output codes representing the conversion iteration count having a step size increasing with the count value and selected to reduce downstream processing.