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The author considers the analog interface functions required in the periphery of information systems. Circuit techniques are discussed with are compatible with monolithic CMOS, bipolar, and BICMOS technologies. Applications are considered in the context of the following functions: input amplifier, filters, signal conditioning, voltage-current convertors, and output (power) amplifier. >

This paper studies the suitability of CMOS device technology for mixed-signal applications. The currently proposed scaling scenario's for CMOS technologies lead to strong degradation of analog transistor performance. As a result the combined optimization of digital and analog devices for system-on-a-chip applications will require increasingly elaborate process modifications. New device solutions such as metal gate integration and asymmetric (source-side-only) workfunction modification offer process options for future mixed-signal CMOS applications.

A novel sense-amplifier circuit suitable for fast and large SRAMs in submicron CMOS technology has been proposed. The sense-amplifier is fast, yet very simple, comprising only four transistors. It features a current-sensing character, since it represents a virtual short-circuit to the bitlines, transferring the cell current directly to the output circuits. Sensing delay is rendered insensitive to bitline capacitance, thus easing one of the constraints in memory architecture design: that of restricted bitline length. Current consumption is decreased and yet speed is improved owing to an intrinsic precharge (or dynamic biasing) property. The virtual short-circuit character ensures equal bitline voltages, thus eliminating the need for bitline equalization during a read-access. This could also significantly affect architecture tradeoffs and chip access time

A circuit implementing an algebraic approximation to the cosine function, valid in all four quadrants with an error of 0.6% will be described. The approximation results in a smooth, differentiable function, without slope discontinuities.