Abstract—This paper discusses architectural and circuit-level aspects related to hardware realizations of fuzzy controllers. A brief overview on fuzzy inference methods is given focusing on chip implementation. The singleton or zero-order Sugeno’s method is chosen since it offers a good tradeoff between hardware simplicity and control efficiency. The CMOS microcontroller described herein processes information in the current-domain, but input–output signals are represented as voltage to ease communications with conventional control circuitry. Programming functionalities are added by combining analog and digital techniques, giving rise to a versatile microcontroller, capable of solving different control problems. After identifying the basic component blocks, the circuits used for their implementation are discussed and compared with other alternatives. This study is illustrated with the experimental results of prototypes integrated in different CMOS technologies. Index Terms—CMOS, fuzzy controllers. I.

The classification of universal amplifiers presented in this paper places all operational amplifiers and current conveyors known from the literature into a common framework, together with abstract concepts such as the universal active element and the nullor. Our approach is new in that we base it on four-terminal theory, which results in a classification that is more extensive but not more complex than classifications derived using two-port theory. It turns out that our classification contains a new type of operational amplifier, which we call current-feedback operational transconductance amplifier (CFB OTA), and also a new class of voltage-inverting current conveyors. We then demonstrate that our classification is very closely related to integrated-amplifier design by showing how all operational amplifiers and current conveyors can be implemented in CMOS using only a few CMOS circuits. Since the basic ideas behind CMOS and bipolar circuits are very similar, this paper is not process specific and can be seen as an attempt to bridge the gap between amplifier theory and amplifier design that has become ever wider in the past few years.

This paper presents mixed-signal current-mode CMOS circuits to implement programmable fuzzy controllers that perform the singleton or zero-order Sugeno's method. Design equations to characterize these circuits are provided to explain the precision and speed that they offer. This analysis is illustrated with the experimental results of prototypes integrated in standard CMOS technologies. These tests show that an equivalent precision of 6 bits is achieved. The connection of these blocks according to a proposed architecture allows fuzzy chips with low silicon area whose inference speed is in the range of 2 Mega FLIPS (fuzzy logic inferences per second). Integrated Circuit Implementation of Fuzzy Controllers 3 I.- Introduction. The use of fuzzy systems is widespread, mainly in the control field. Most fuzzy microcontrollers presently used in industrial applications are digital implementations. However, fuzzy logic is intrinsically more like the multivalued and continuous analog world th...

ACMOS continuous time current-mode circuit which provides the maximum of n analog inputs is presented. This structure exhibits a O(n) complexity, and allows high precision and speed with small area and very low power dissipation. Its operation is discussed and illustrated with simulation results. INTRODUCTION Multiple-input Max/Min circuits are basic building blocks in many advanced computational systems, such as fuzzy or artificial neural networks. Solutions have been reported where the physical variable carrying on the information is either current or voltage. Hardware implementations which take voltages as inputs are generally based on operational amplifiers that means complex circuit blocks. More promising for VLSI are currentbased implementations, which fall into one of four approaches: a) cascaded realizations of two-input operators [1], which tend to introduce large delays when the number of inputs increases; b) circuits of O(n 2 ) complexity with positive feedback [2]; c) str...

The paper presents the design and analyzes the applications of a microsystem to be used for emulating, in real time, early vision tasks, such as stereo depth estimation and motion analysis. All the required computations are based on linear filtering operations with Gabor-like kernels. Full control on the parameters (phase, frequency, and spatial extension) of the kernel can be obtained by introducing a 2ndorder 1-D lattice network that can be mapped with efficiency on an array of simple cells, implemented as analog CMOS VLSI circuits, using continuously adjustable transconductors. I. Introduction Analog approaches to the hardware implementation of machine vision systems can be very effective as far as realtime performance, size, and power consumption are concerned, but machine functionality, with regard both to the variety of tasks to be performed, and to the conditions of application, can be hindered by the limited flexibility and lack of programmability of analog circuits. A soluti...