Browse Prior Art Database

Method of Improving Card System Manufacturing Throughput in a VME/VSB Test Environment

IP.com Disclosure Number: IPCOM000109733D
Original Publication Date: 1992-Sep-01
Included in the Prior Art Database: 2005-Mar-24
Document File: 4 page(s) / 180K

Publishing Venue

IBM

Related People

Carini, R: AUTHOR [+3]

Abstract

This program allows for greater throughput of individually tested 6095 cards. This then translates into greater confidence in system reliability and reduced manufacturing skill levels.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 37% of the total text.

Method of Improving Card System Manufacturing Throughput in a VME/VSB Test Environment

       This program allows for greater throughput of
individually tested 6095 cards.  This then translates into greater
confidence in system reliability and reduced manufacturing skill
levels.

      This invention provides a method of improving the manufacturing
capability of 6095 VME/VSB cards.  The program of increasing card
(and therefore system) yields is achieved through on-board diagnostic
extensions and specially designed backplanes.  As a result of these
activities, the manufacturing skill level required in the
interpretation of test results is also decreased.

      This program was designed to improve test yields for the cards
of the 6095 Graphics Processor.  The configuration of the 6095 is
shown in the drawing.  As can be seen, the 6095 consists of a
backplane, base (i.e., required) and feature card types that connect
to the backplane, a disk interface, a fiber-optic peripheral
interface and a diagnostic status panel display.  The testing of the
6095 is performed in stages.  The stages are as follows:
1)   ATE Test - individual component testing (bed of nails)
2)   SQV Test - initial unit testing
3)   ESS Test - environmental stress testing
4)   Final Test - disk and peripheral testing
5)   Visual Test - screen attributes testing
6)   SAK Test - software/hardware testing

      The stage that was having the highest fallout rate was ESS
test.  The unit is being stress tested.  This area is expected to
have the highest fallout rate, but additional fallout was occurring
due to the test methods that were being employed in the test chamber.
The paragraphs which follow describe the methods that were employed
in the past, the shortcomings of the test methods, and the
improvements that were made.
Complete Unit ESS Test Method

      The 6095 was initially tested in the ESS chamber as a complete
system.  The slots were filled with the base configuration card types
as well as a number of feature card types.  The number of feature
card types that were tested had to be estimated using both actual and
estimated orders for the feature as well as an estimate of the number
of cards that would fall out during testing.  This fall-out estimate
is applied to base configuration card types also.  In order for the
system to pass this stage of testing, the entire unit had to complete
the ESS test cycle error free.  If a unit had a failure, the entire
unit was failed, the faulty card fixed and the unit was again
scheduled for a pass through the ESS Test process.
Problems with Unit Test Method

      Throughput and Stress:  What was noticed was that for a failed
unit, there was usually only one card of the unit which was faulty
and the faulty card was being called out successfully by the on-board
diagnostics.  However, there was no way of being completely sure that
the card being called out was the only card with pro...