Browse Prior Art Database

Array Multiplexing Arrangement

IP.com Disclosure Number: IPCOM000047190D
Original Publication Date: 1983-Oct-01
Included in the Prior Art Database: 2005-Feb-07
Document File: 3 page(s) / 50K

Publishing Venue

IBM

Related People

McCurry, RE: AUTHOR

Abstract

In matrix printing and memory applications it is desirable to reduce the number of drivers required to provide access to a large array of print or memory elements. The usual approach with an array of "two-terminal devices" is to arrange the wiring so that if there are Q devices one can approach 2 Q drivers. It has been found possible to further reduce the number of drivers for large arrays if the devices are "M-terminal devices" where M>2. Consider a linear array of two-terminal devices, for example, magnetic print heads consisting of a pole piece 10 and one turn of wire 11 (Fig. 1). For our purpose, only the number of terminals is of interest. We see in Fig. 2 how this array can be optimally wired for multiplexing. In Fig.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 3

Array Multiplexing Arrangement

In matrix printing and memory applications it is desirable to reduce the number of drivers required to provide access to a large array of print or memory elements. The usual approach with an array of "two-terminal devices" is to arrange the wiring so that if there are Q devices one can approach 2 Q drivers. It has been found possible to further reduce the number of drivers for large arrays if the devices are "M-terminal devices" where M>2. Consider a linear array of two-terminal devices, for example, magnetic print heads consisting of a pole piece 10 and one turn of wire 11 (Fig. 1). For our purpose, only the number of terminals is of interest. We see in Fig. 2 how this array can be optimally wired for multiplexing. In Fig. 2 along the bottom we have G' independent "wires" out for drivers and each of the wires makes G device terminals of array A common. We can refer to the G' as horizontal or H driver terminals. The opposing set of device terminals, labeled B, is arranged so that the corresponding terminals of each of the H array set are connected in common. Hence, the B terminal of device 1 in set 1' is connected to the B terminal of device 1 in set 2', etc., up to the B terminal of device 1 in set G'. The vertical or V array of terminals, labeled 1 through G, can then be connected to a power supply by G controllable drivers while the G' H array is connected to ground by means of G' drivers. It is then possible to "write" a magnetic image on a drum or tape by control of the N = G + G' drivers; it can be simply shown that in the ideal case the minimum number of drivers is obtained by selecting G = Q. Since Q may not be a perfect square, in practice one may have to choose G to be larger than Q, possibly just rounded up by one driver. In this case G' may be rounded down or up so that G x G' > Q. The foregoing is believed to be well known. What is believed new is that it is possible to further reduce the number of drivers by, for example, adding another turn of wire in the magnetic print head case, to each pole and setting the current levels low enough so that current must flow in both coils in order to writ...