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.

For applications involving the control of moving vehicles, the recovery of relative motion between a camera and its environment is of high utility. This thesis describes the design and testing of a real-time analog vlsi chip which estimates the focus of expansion (foe) from measured time-varying images. Our approach assumes a camera moving through a fixed world with translational velocity; the foe is the projection of the translation vector onto the image plane. This location is the point towards which the camera is moving, and other points appear to be expanding outward from. By way of the camera imaging parameters, the location of the foe gives the direction of 3-D translation. The algorithm we use for estimating the foe minimizes the sum of squares of the differences at every pixel between the observed time variation of brightness and the predicted variation given the assumed position of the foe. This minimization is not straightforward, because the relationship between the brightn...

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...

In this paper, a compact low-power (LP) low-voltage (LV) metal--oxide--semiconductor-only (MOS-only) variable gain amplifier (VGA) is introduced. This amplifier based on complementary MOS (CMOS) transistors operating in strong inversion is composed of a pseudo-exponential current-to-voltage converter, analog multiplier, and output stage. The gain of the amplifier is controlled exponentially by a novel wide-range pseudoexponential current-to-voltage converter implemented with two back-to-back connected current mirrors exhibiting superb exponential characteristic. Also, a new LV/LP composite transistor is introduced to increase the input dynamic range of the multiplier. The amplifier is fabricated using a 2-m MOSIS n-well process, and its simulation and measurement results are shown in detail. I. INTRODUCTION A LTHOUGH lower supply voltage directly translates to lower power consumption in digital circuits, a similar conclusion cannot necessarily be drawn for analog circuits. Therefore...

s [1]. The motivation for this research and some of its main recent results ([9]-[13]) is the subject of the oral presentation. The main subjects to be addressed are: 1 Now with Philips Semiconductors, Nijmegen, The Netherlands ffl The motivation for the use of transconductance based CMOS Circuits. Important issues are electronic variability, high-frequency behaviour, matching and the range of achievable transconductance values. ffl The aim of the development of systematic circuit generation, classification and analysis techniques for these circuits. ffl An example of an AGC amplifier design based on a systematic generation of alternative circuit topologies. It will be shown that many alternative circuits are possible. These circuits appear to have specific strong and weak points in different mixes. As a result the availability of a set of alternative topologies is attractive. ffl A classification system for two-po

Abstract.-The bipolar transconductance amplifier (OTA) was commercially introduced in 1969 by RCA. Designers began using OTAs in the middle 80’s, since then the CMOS-OTA has becoming a vital component in a number of electronic circuits, both in open loop and in closed loop applications. Here, we will focus on open loop applications. Continuous-time filters implemented with transconductance amplifiers and capacitors known as Gm-C or OTA-C are very popular for a host of applications. These applications involve frequency of operation from a few tents of a hertz up to several gigahertz. Several of those applications are in medical electronics and seismic area where the frequency range is between 0.1Hz up to 20Hz. Other applications in the audio range do not commonly use OTA-C filters because switched-capacitor techniques excel in this range. But for frequency range of a few MHz like in Intermediate Frequency (IF) filters in RF receivers OTA-C implementations are very attractive. For a few GHz range applications where the OTA becomes a simple differential pair there is number of researchers investigating LC-oscillators and filters. In this tutorial we discuss practical implementations of transconductance amplifiers oriented for wide range of applications for example in medical, IF filters, hard disk drive linear phase filters, LC-oscillators and RF filters. Furthermore the unavoidable tuning scheme to compensate the Gm/C deviations due to process technology variations is discussed. OTA single ended, fully differential and pseudo differential versions are introduced together with the commonmode feedback circuits needed for proper operation of differential architectures. Continuous-Time Filters from 0.1Hz to 2.0GHz Outline.-