The Effects of Interconnections on High-Speed Logic Circuits
TL;DR: It is shown that high-speed circuitry must be miniaturized and the implications are discussed.
Abstract: By way of worked examples in typical but somewhat idealized cases the effect on circuit speed of circuit interconnections is studied. The source, calculation and minimization of interconnection crosstalk is also discussed. It is shown that high-speed circuitry must be miniaturized and the implications are discussed.
Citations
More filters
01 May 1998
TL;DR: One primary result of this study is evidence demonstrating that a range for the length of the interconnect exists for which inductance effects are prominent and it is shown that under certain conditions, inductancy effects are negligible despite thelength of the section of interconnect.
Abstract: A closed form solution for the output signal of a CMOS inverter driving an RLC transmission line is presented. This solution is based on the alpha power law for deep submicrometer technologies. Two figures of merit are presented that are useful for determining if a section of interconnect should be modeled as either an RLC or an RC impedance. The damping factor of a lumped RLC circuit is shown to be a useful figure of merit. The second useful figure of merit considered in this paper is the ratio of the rise time of the input signal at the driver of an interconnect line to the time of flight of the signals across the line, AS/X circuit simulations of an RLC transmission line and a five section RC II circuit based on a 0.25 /spl mu/m IBM CMOS technology are used to quantify and determine the relative accuracy of an RC model. One primary result of this study is evidence demonstrating that a range for the length of the interconnect exists for which inductance effects are prominent. Furthermore, it is shown that under certain conditions, inductance effects are negligible despite the length of the section of interconnect.
142Â citations
Cites result from "The Effects of Interconnections on ..."
...Note that if in (9) is squared, this figure of merit becomes a comparison between the time constant and the time constant RC, which is the same result as described in [1], [3], and [16]....
[...]
IBM1
TL;DR: A coherent survey of the modeling and computer-aided design techniques applicable to solving hardware problems with the advent of smaller and denser integrated circuits and packages is given.
Abstract: In the last decade an important shift has taken place in the design of hardware with the advent of smaller and denser integrated circuits and packages. Analysis techniques are required to ensure the proper electrical functioning of this hardware. In this paper we give a coherent survey of the modeling and computer-aided design techniques applicable to solving these problems. Methods are considered for the computation of resistances, capacitances, and inductances. Also, an extensive list of references is given.
122Â citations
TL;DR: This paper proves that a signal introduced at one end of a printed wire above a ground plane in the presence of a second parallel (passive) wire must break up into two signals traveling at different velocities.
Abstract: As digital system speeds increase and their sizes diminish, it becomes increasingly important to understand the mechanism of signal crosstalk (noise) in interconnections between logic elements. The worst case is when two wires run parallel for a long distance. Past literature has been unsuccessful in explaining crosstalk between parallel wires above a ground plane, because it was assumed that only one signal propagation velocity was involved. This paper proves that a signal introduced at one end of a printed wire above a ground plane in the presence of a second parallel (passive) wire must break up into two signals traveling at different velocities. The serious crosstalk implications are examined. The new terms slow crosstalk (SX), fast crosstalk (FX) and differential crosstalk (DX) are defined.
99Â citations
01 Jun 1999
TL;DR: Closed form solutions for the 50% delay, rise time, overshoots, and settling time of signals in an RLC tree are presented, which have the same accuracy characteristics as the Elmore delay model for RC trees and preserves the simplicity and recursive characteristics of theElmore delay.
Abstract: Closed form solutions for the 50% delay, rise time, overshoots, and settling time of signals in an RLC tree are presented, These solutions have the same accuracy characteristics as the Elmore delay model for RC trees and preserves the simplicity and recursive characteristics of the Elmore delay. The solutions introduced here consider all damping conditions of an RLC circuit including the underdamped response, which is not considered by the classical Elmore delay model due to the non-monotone nature of the response. Also, the solutions have significantly improved accuracy as compared to the Elmore delay for an overdamped response. The solutions introduced here for RLC trees can be practically used for the same purposes that the Elmore delay is used for RC trees.
91Â citations
TL;DR: Several analytical techniques are described for predicting the kinds of reflections and crosstalk that are typically seen in digital systems, thus enabling the engineer to determine in advance whether or not such ``interconnection noise'' will result, how bad it will be, and what the typical interconnection limitations are for circuits of various speeds.
Abstract: Digital logic circuits are now available and are being used with delay times that are comparable to the delays of interconnections used in packaging these circuits. At high speeds, however, such interconnections no longer behave as simple short circuits, but take on the appearance of transmission lines. Unless transmission lines are terminated properly, ``reflections'' can develop that might be of sufficient magnitude to produce false logic levels or exceed maximum circuit voltage specifications. One may choose to solve the problem by increasing the density of the system. This, however, introduces the problem of ``crosstalk.'' The present article describes several analytical techniques for predicting the kinds of reflections and crosstalk that are typically seen in digital systems, thus enabling the engineer to determine in advance whether or not such ``interconnection noise'' will result, how bad it will be, and what the typical interconnection limitations are for circuits of various speeds.
86Â citations
References
More filters
01 Nov 1954
TL;DR: In this article, a simple configuration of four wires (or two wires and ground) can serve simultaneously as a directional coupler, filter, and transformer, and the coupled lines may be of equal or different impedance.
Abstract: The natural coupling between parallel transmission lines is inherently directional. Very simple and cheap directional couplers can be made which utilize this effect. By introducing appropriate variation of coupling with distance a wide variety of transmission characteristics may be realized, including high-pass (ideally, infinite bandwidth) characteristics. The coupled lines may be of equal or different impedance. Thus, a simple configuration of four wires (or two wires and ground) can serve simultaneously as a directional coupler, filter, and transformer.
215Â citations
IBM1
TL;DR: This computer, like the 704, is aimed at scientific problems such as reactor design, hydrodynamics problems, partial differential equations etc., its instruction set and organization are such that it can handle with ease data-processing problems normally associated with commercial applications, such as processing of alphanumeric fields, sorting, and decimal arithmetic.
Abstract: The Stretch Computer project was started in order to achieve two orders of magnitude of improvement in performance over the then existing 704. Although this computer, like the 704, is aimed at scientific problems such as reactor design, hydrodynamics problems, partial differential equations etc., its instruction set and organization are such that it can handle with ease data-processing problems normally associated with commercial applications, such as processing of alphanumeric fields, sorting, and decimal arithmetic.
76Â citations
[...]
TL;DR: This paper gives a brief description of work originating in the Computer Group at Manchester University, the name given to a large computing system which can include a variety of peripheral equipments, and an extensive store.
Abstract: This paper gives a brief description of work originating in the Computer Group at Manchester University. Atlas is the name given to a large computing system which can include a variety of peripheral equipments, and an extensive store. All the activities of the system are controlled by a program called the supervisor. Several types of store are used, and the addressing system enables a virtually unlimited amount of each to be included. The primary store consists of magnetic cores with a cycle time of under two microseconds, which is effectively reduced by multiple selection mechanisms. The core store is divided into 512 word "pages"; this is also the size of the fixed blocks on drums and magnetic tapes. The core store and drum store are addressed identically, and drum transfers are performed automatically as described in Section 3. There is a fixed store which consists of a wire mesh into which ferrite slugs are inserted; it has a fast read-out time, and is used to hold common routines including routines of the supervisor. A subsidiary core store is used as working space for the supervisor. The V-store is a collective name given to various flip-flops throughout the computer, which can be read, set, and re-set by reading from or writing to particular store addresses.
28Â citations
Book•
[...]
01 Nov 2001
TL;DR: In this article, a brief description of work originating in the Computer Group at Manchester University is given, where the core store is divided into 512 word "pages"; this is also the size of the fixed blocks on drums and magnetic tapes.
Abstract: This paper gives a brief description of work originating in the Computer Group at Manchester University. Atlas is the name given to a large computing system which can include a variety of peripheral equipments, and an extensive store. All the activities of the system are controlled by a program called the supervisor. Several types of store are used, and the addressing system enables a virtually unlimited amount of each to be included. The primary store consists of magnetic cores with a cycle time of under two microseconds, which is effectively reduced by multiple selection mechanisms. The core store is divided into 512 word "pages"; this is also the size of the fixed blocks on drums and magnetic tapes. The core store and drum store are addressed identically, and drum transfers are performed automatically as described in Section 3. There is a fixed store which consists of a wire mesh into which ferrite slugs are inserted; it has a fast read-out time, and is used to hold common routines including routines of the supervisor. A subsidiary core store is used as working space for the supervisor. The V-store is a collective name given to various flip-flops throughout the computer, which can be read, set, and re-set by reading from or writing to particular store addresses.
27Â citations
01 Jan 1960
18Â citations