Multiple topics which all focus on precision monolithic circuit design but beyond this are not directly related to each other are presented. The first topic is a digital tuning scheme for digitally programmable integrated continuous-time filters (4), (8) - (10). Emphasis of this research is on development of a more general tuning scheme which can be applicable to various filter functions as well as high-frequency applications. The tuning scheme consists of two phases: system identification and adjustment. Various continuous-time filter identification methods including time-domain and frequency-domain approaches are investigated, and a filter adjustment algorithm is presented. Potential of high accuracy of the proposed tuning scheme and successful applicability to high-frequency filters with versatile functions have been demonstrated through simulations and experiments;Four other topics are separately presented. First, nonidealities associated with high-precision amplifiers (5), (7) are discussed. Special emphasis is given on analysis of statistical characteristics of random CMRR and offset of CMOS op-amps which can help estimating yield of high-volume production and help engineers design for a given yield. Next, an automatic offset compensation scheme for CMOS op-amps with ping-pong control (2), (6) is presented. A very low-voltage circuit design technique using floating gate MOSFETs (3) is introduced. Finally, an accurate and matching-free threshold voltage extraction scheme using a ratio-independent SC amplifier and a dynamic current mirror (1) is discussed.