A Digital-Based Analog Differential Circuit

A novel, digital-in-concept approach in the design of analog differential circuits, suitable to very low voltage, aggressively scaled, pure digital integrated circuit technologies, is explored in this paper. A differential stage based on the proposed technique is presented and its operation as a voltage comparator and as an operational amplifier in negative feedback configurations is discussed and demonstrated on the basis of theory and simulations. The practical feasibility of the proposed approach is finally verified by experiments carried out on a proof-of-concept prototype.