Browse Prior Art Database

Electrical Overload Protection in LSI Device Readout

IP.com Disclosure Number: IPCOM000045885D
Original Publication Date: 1983-Apr-01
Included in the Prior Art Database: 2005-Feb-07
Document File: 2 page(s) / 28K

Publishing Venue

IBM

Related People

Yu, CC: AUTHOR

Abstract

Electrical overload (EOL)-induced failure may occur during LSI device readout using automatic testers. Sometimes, failures of this type are indistinguishable from those induced by life test, and consequently important reliability information is lost. EOL-induced failures can be minimized by inserting on-chip devices that are not susceptible to EOL failure between the input signals and the devices under test.

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 99% of the total text.

Page 1 of 2

Electrical Overload Protection in LSI Device Readout

Electrical overload (EOL)-induced failure may occur during LSI device readout using automatic testers. Sometimes, failures of this type are indistinguishable from those induced by life test, and consequently important reliability information is lost. EOL-induced failures can be minimized by inserting on-chip devices that are not susceptible to EOL failure between the input signals and the devices under test.

The figure shows a test setup for a device under test (DUT) in which forcing electrical signals are applied at device pads A and B (voltage), and C and D (current) . Tester current meters M(A) and M(B) measure the currents out of A and B, and voltage meters M(C) and M(D) measure sure the voltages at C and
D. These elements of the setup are conventional.

In addition to the conventional elements, this setup includes passive on-chip elements E(A), E(B), E(C), and E(D) inserted between the forcing electrical signals and the device pads. E(A), E(B), E(C), and E(D) are devices not susceptible to EOL. At current-forcing needs, E(C) and E(D) can be resistors; at voltage forcing needs, E(A) and E(B) can be small value resistors or forward- biased diodes. Additional voltage meters M(AA) and M(BR) may be added to measure the exact voltage at A and B. The same anti-EOL elements (E(A), E(B),..) can be used repeatedly to protect different devices on the same chip.

1

Page 2 of 2

2

[This page contains 3 pictures or other n...