Browse Prior Art Database

Module Level Redundancy

IP.com Disclosure Number: IPCOM000089673D
Original Publication Date: 1977-Dec-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 26K

Publishing Venue

IBM

Related People

Steiner, PF: AUTHOR

Abstract

This article describes a way of using 1/2 good chips to significantly increase bit productivity without impacting card or system design.

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 74% of the total text.

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Module Level Redundancy

This article describes a way of using 1/2 good chips to significantly increase bit productivity without impacting card or system design.

The chips are divided up into two sections that can be powered up and addressed individually by providing separate chip pads for the +V supply plus the high order address VG1 and VG2. If defects occur on one of the two sections of the chip 14, that section can be bypassed by using a suitably designed substrate 16 that will permit the good section to be used. The substrate is designed to disconnect the +V supply from the defective section of the chip, as shown by the break 10 in the +V supply line 12 of the figure, and connect it to a good section of a second chip 20. The substrate 16 also disconnects the appropriate VG line from the defective section of chip 14, indicated by the break 18 in the VG1 line. The substrate 16 also connects the VG1 line to a good section of the redundant chip 20, and simultaneously grounds the disconnected VG1 connector of the defective chip section of chip 14.

In this way good chips do not pay the penalty of having unnecessary redundancy circuitry on the chip. Also, chip size for this approach is 10-12% smaller than with on-chip redundancy. Moreover, the concept of powering down and bypassing defective chip sections can be used in any chip design. The degree of subdivision is expandable to 3/4, 1/4, etc. Also, there are various ways of achieving any configuration of half good...