Browse Prior Art Database

Core Memory Array Short Circuit Tester

IP.com Disclosure Number: IPCOM000090928D
Original Publication Date: 1969-Aug-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Van Cleave, GW: AUTHOR

Abstract

The device determines short circuits between array lines of a core memory having diodes normally connected between many of the lines to be tested. When a short circuit exists, the output of an oscillator is grounded which in turn signals an alarm circuit.

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Core Memory Array Short Circuit Tester

The device determines short circuits between array lines of a core memory having diodes normally connected between many of the lines to be tested. When a short circuit exists, the output of an oscillator is grounded which in turn signals an alarm circuit.

Transistors T1 and T2 and their associated components form a 16 KC oscillator which produces a .5 volt Peak-to-Peak open circuit signal at rotary switch 11. The oscillator also supplies a 5 volt peak-to-peak signal to the base of transistor T3 allowing T3 to charge capacitor 13 on the negative oscillator swings and thus turn on transistor T4. When T4 is on, transistor T5 is off and light 15 is off.

Switch 11 connects the oscillator output to a selected core memory line 16 and connects all other lines 17 to ground. If a short exists between the selected line and any other line, the oscillator signal is grounded. The oscillator is thus stopped, turning T3 and T4 off, T5 on, and lamp 15 on indicating the short. The short is thus detected without regard to the diode connections on the various lines of the core memory.

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