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This paper presents a novel method for the design of analog integrated circuit, making use of fixator–norator pairs for the performance design and biasing design. Fixators are the distinctive tools for setting a critical design parameter at a desired value whereas the pairing norator renders these critical parameters into adequate supporting components, mainly resistors. For analog ICs, active loads and current mirrors serve as supporting components. Hence, the use of fixator–norator pairs may abbreviate as defining the dynamic and static resistance of active loads and current mirrors that should be affirmative with a given design. The proposed methodology is illustrated by the use of a common emitter amplifier, a BJT differential amplifier, a MOS operational amplifier and a three-stage CMOS operational amplifier.

This paper describes a high-performance impedance measurement circuit for the application of skin impedance measurement in the early detection of skin cancer. A CMRR improvement technique has been adopted for OTAs to reduce the impact of high-frequency common mode interference. A modified three-OTA instrumentation amplifier (IA) has been proposed to help with the impedance measurement. Such systems offer a quick, noninvasive and painless procedure, thus having considerable advantages over the currently used approach, which is based upon the testing of a biopsy sample. The sensor has been implemented in 65nm CMOS technology and post-layout simulations confirm the theoretical claims we made and sensor exhibits sensitivity. Circuit consumes 45uW from 1.5V power supply. The circuit occupies 0.01954mm² silicon area.

We introduce a clear constructive methodology of approximation and synthesis of analog functions using the transfer characteristics of the basic differential pair. The new methodology provides circuit designers with an easy-to-understand solution of the function approximation problem employing MOSFETs in weak inversion. It further provides compact formulas for the optimal coefficients involved in the approximation. We confirm the design methodology using SPICE through two examples involving the exponential function.