Abstract: An element, the position of which it is desired to sense, controls the illumination of a charge transfer register. In one embodiment, for example, the element controls the position of a mask between a light source and a linear CCD array to thereby control the number of CCD stages which will receive photon induced charge signals. These signals, when shifted out of the register, may be employed directly as a digital manifestation indicative of position or may be converted to another form of such a manifestation.

Abstract: A voltage controlled oscillator which, for example, may be utilized in a phase locked loop, includes an odd number (n) of cascaded COS-MOS inverter stages with a feedback path coupling the output of the last stage to the input of the first stage to form a ring configuration. The ring configuration oscillates at a frequency f.sub.1 determined by the transconductances of the inverter stages and the shunt capacitances between the stages. Signals comprising impulses of current having frequency components at f.sub.1 and 2f.sub.1 flow through the power supply inputs of each of the stages as they successively are switched from one state to another. A frequency selective impedance path is coupled between a source of power supply voltage and the power supply inputs of each of the stages to develop a second signal having a frequency f.sub.2 equal to a multiple nf.sub.1 or 2nf.sub.1. The voltage applied to the commonly connected power supply inputs may be controlled to control f.sub.1 and, consequently, f.sub.2.