Some open issues associated with the new type of component: digital-to-frequency converter [Open Column]

This paper presents seven unsolved mathematical problems which all relate to a new type of electronic component: digital-to-frequency converter. These problems are parts of the theoretical foundation of this new component. Even though theoretical in nature, these problems will have profound impact on future real electronic system design. These problems present themselves as an excellent example of demonstrating the significance of mathematical analysis in circuit design applications. They show the importance of fundamental research on directing the real world work.