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

VLSI Functional Vehicle for a Junction Temperature Measurement Technique

IP.com Disclosure Number: IPCOM000043991D
Original Publication Date: 1984-Oct-01
Included in the Prior Art Database: 2005-Feb-05
Document File: 2 page(s) / 47K

Publishing Venue

IBM

Related People

Petrie, B: AUTHOR [+2]

Abstract

This article describes a method which measures the junction temperature (Tj) of a functional VLSI product and the Tj changes in response to AC/DC applied conditions in a dynamic realtime test environment. A row address select (RAS) protect diode is used as the vehicle for temperature measurement. The method also allows automatic control of the ambient case temperature (Ta) to a VLSI product to keep a fixed Tj under all test conditions (vary Ta). This method provides direct Ta-to-Tj correlation during development testing before card or systems level testing (or as a failure analysis diagnostic tool). The forward bias (Vf) test on the RAS protect diode is used as the measurement vehicle because it is not connected to any other pad/pin on a module.

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 57% of the total text.

Page 1 of 2

VLSI Functional Vehicle for a Junction Temperature Measurement Technique

This article describes a method which measures the junction temperature (Tj) of a functional VLSI product and the Tj changes in response to AC/DC applied conditions in a dynamic realtime test environment. A row address select (RAS) protect diode is used as the vehicle for temperature measurement. The method also allows automatic control of the ambient case temperature (Ta) to a VLSI product to keep a fixed Tj under all test conditions (vary Ta). This method provides direct Ta-to-Tj correlation during development testing before card or systems level testing (or as a failure analysis diagnostic tool). The forward bias (Vf) test on the RAS protect diode is used as the measurement vehicle because it is not connected to any other pad/pin on a module. Other pads/pins could be used depending on the product design of the random-access memory or the logic VLSI product. A hand-held heat probe (or oven fixture) is applied to the product case (cap). The environment Ta is established in this manner for a long period of time so that the thermal mass time constants do not affect the data. This time constant includes the test socket and/or test fixture. Additional power can be gathered by applying DC power and AC clock cycles. The measurement interval must be done in a small fraction of the time compared to the powered-on condition. The figure shows a 6-second AC/DC power-on with a 150-millisecond ramp off/...