Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Resistor Transistor Selection Matrix for Gas Discharge Panel

IP.com Disclosure Number: IPCOM000086078D
Original Publication Date: 1976-Jul-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 2 page(s) / 42K

Publishing Venue

IBM

Related People

Davis, GT: AUTHOR

Abstract

One of the methods heretofore employed to drive a gas panel utilizes a diode resistor selection matrix and driver configuration, composed of bit and group drivers which are selectively fired. In larger panels the number of diodes in the matrix to be controlled by one driver is significant. When a single panel line is selected, the nonselected diodes are reverse biased and constitute a capacitive load which must be charged up to write or erase on the panel.

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 53% of the total text.

Page 1 of 2

Resistor Transistor Selection Matrix for Gas Discharge Panel

One of the methods heretofore employed to drive a gas panel utilizes a diode resistor selection matrix and driver configuration, composed of bit and group drivers which are selectively fired. In larger panels the number of diodes in the matrix to be controlled by one driver is significant. When a single panel line is selected, the nonselected diodes are reverse biased and constitute a capacitive load which must be charged up to write or erase on the panel.

For some panel sizes, the effect of load capacitance can be more than doubled because of this diode capacitance. Such capacitance will either increase the rise times of the drive signals beyond operating margins or larger panel drivers will be required to provide the increased charge current; larger drivers, in turn, mean larger chip area, more power dissipation, lower yields and increased costs.

The described circuit configuration replaces each bit driver of the diode selection matrix by an individual driver for each line, but all of the drivers for one bit are turned on and off simultaneously. Referring to Fig. 1, one embodiment of the circuit utilizes a single NPN transistor shown as transistors 3, 5, 7 and 9 for each driver. A PNP transistor, a three junction device or a multidevice driver could replace the NPN transistors depending upon the application. The transistors have a common base connection to logical input line 11 so that logically they all perform as a single driver. However, electrically the presence of individual drivers serves to isolate the asso...