Transcript Jedec Standards

JEDEC Standards
-Nicole Okamoto and Widah Saied
All figures from Jedec Standard JESD51-12
www.jedec.org
JEDEC Introduction
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JEDEC was founded in 1960 and stands for the Joint
Electron Device Engineering Council.
JEDEC is the standardization body of the Electronic
Industries Alliance, which helps develop standards on
electronic components, consumer electronics, electronic
information, telecommunications, and internet security.
JEDEC issues often used standards for device interfaces,
such as RAM and DDR SDRAM(double-data-rate
synchronous dynamic random access memory), which is a
type of memory in integrated circuits used in computers.
Wikipedia,http://en.wikipedia.org/wiki/JEDEC
JEDEC Introduction
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JEDEC Philosophy:JEDEC standards and publications are designed to
serve the public interest through eliminating misunderstandings
between manufacturers and purchasers, facilitating interchangeability
and improvement of products.
JEDEC has 2700 participants, appointed by 270 companies work in 50
committees. The world community accepts the publications and
standards that they generate.
Jedec, http://www.jedec.org/
Examples of standards
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JESD 22-A103C HIGH TEMPERATURE STORAGE LIFE:
The test is applicable for evaluation, screening, monitoring,
and/or qualification of all solid state devices.
High Temperature storage test is typically used to determine
the effect of time and temperature, under storage
conditions, for thermally activated failure mechanisms of
solid state electronic devices
During the test elevated temperatures (accelerated test
conditions) are used without electrical stress applied.
Examples of standards
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JESD 22-A104C TEMPERATURE CYCLING: This standard provides a
method for determining solid state devices capability to withstand extreme
temperature cycling.
JESD 22-A106B
THERMAL SHOCK: This test is conducted to determine the resistance
of a part to sudden exposure to extreme changes in temperature and
to the effect of alternate exposures to these extremes.
JESD 51 Methodology for the Thermal
Measurement of Component Packages
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JESD51-1 Integrated Circuit Thermal Measurement Method – Electrical Test
Method
JESD51-2 Integrated Circuit Thermal Test Method Environmental Conditions –
Natural Convection
JESD51-3 Low Effective Thermal Conductivity Test Board for Leaded Surface
Mount Packages
JESD51-4 Thermal Test Chip Guideline
JESD51-5 Extension of Thermal Test Board Standards for Packages with Direct
Thermal Attachment Mechanisms
JESD51-6 Integrated Circuit Thermal Test Method Environmental Conditions –
Forced Convection
JESD51-7 High Effective Thermal Conductivity Test Board for Leaded Surface
Mount Packages
JESD 51 cont.
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JESD51-8 Integrated Circuit Thermal Test Method Environmental Conditions –
Junction to Board
JESD51-9 Test Boards for Area Array Surface Mount Package Thermal
Measurements
JESD51-10 Test Boards for Through-Hole Perimeter Leaded Package Thermal
Measurements
JESD51-11 Test Boards for Through-Hole Area Array Leaded Package Thermal
Measurements
JESD51-12 Guidelines for Reporting and Using Electronic Package Thermal
Information
JESD 22-A103C High Temperature Storage Life
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Scope: Determine the effect of time and temperature, under storage
conditions, of thermally activated failure mechanisms of solid state
electronic devices.
Jedec Standard,http://www.jedec.org/download/search/22a103c.pdf
Apparatus of Test
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The apparatus is a temperature controlled chamber
capable of maintaining the entire sample population
at a specified testing temperature.
Method of Testing
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The samples will be stored at one of the temperature conditions
given in Table 1:
Table 1: High Temperature Storage Conditions
Condition A: +125(-0/+10) ºC
Condition B: +150(-0/+10) ºC
Condition C: +175(-0/+10) ºC
Condition D: +200(-0/+10) ºC
Condition E: +250(-0/+10) ºC
Condition F: +300(-0/+10) ºC
Condition G: +85(-0/+10) ºC
Method of Testing
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Typically, the sample is tested under condition B for 1000 hours, but
other conditions or durations may be used.
Note: the rate of temperature increase should be low to prevent
overstress of the sample that would not occur under normal conditions.
The failure criteria for a sample is:
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The part can no longer function as designed
Cracking, chipping, or breaking of the package as long as the package
performance was critical to the performance of the sample. However, if the
damage was due to fixtures or handling, then failure is not attributed to
the test.
Method of Testing
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Things to be specified:
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Sample size and number of failures
Time and conditions
Whether intermediate measurements were taken
JESD51-12 Guidelines for Reporting and Using Electronic
Package Thermal Information
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qJA junction-to-still ambient air resistance (natural convection
q JA 
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Tj  Ta
P
qJMA junction-to-moving air resistance (forced convection)
Deviations During Application
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Results during application may vary since the
application may differ from the following test
conditions:
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Power dissipation
Air velocity, direction, turbulence
Power and number of adjacent components and boards
PCB orientation and size
Two-sided vs. one-sided mounting
Die size
Copper trace thickness and widths
Environment (for example, natural convection tests are done
in a chamber 1 ft3)
Conduction resistances
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qjctop, qjcbot – junction to top of case and bottom of
case resistances, respectively
q JCx
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qjb – junction to board resistances
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TJ  Tcase
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P
Leaded package: measure Tboard to foot of lead
Surface mount package: measure board trace within 1
mm of package
These resistances are found by forcing all of the
heat flow to go out the respective surface, which
may not match reality
Thermal Characterization Parameter
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ΨJT – junction to top thermal characterization
ΨJB – junction to board thermal characterization
The equations are the same as those for thermal
resistance q except that the power P is now the total
power, not just the power in that direction. For
example, if only 5% of your total heat loss is down
through the PCB, your P would still be your total
power.
These can help with estimates of junction
temperature for object already under use where
temperatures can be measured and there is no heat
sink present (instead of for the design phase)
Compact Models
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Two-resistor model: good for hand calculations but
not really accurate
DELPHI Compact Models
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These are mathematical models, not thermal
resistance model
Provided by some component manufacturers
Effect of Package Construction on
Thermal Results
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2s0p: two signal planes, zero power planes on
laminate substrate for plastic ball grid array packages
Added copper improves performance
Effect of PCB Design
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More copper to spread heat means better
performance.
Effect of Multiple Packages
Effect of PCB size
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On setups where a lot of heat is carried away by the
copper in the PCB, the larger the PCB the better the
performance – more heat transfer area.
Effect of Die Size
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For the same power, larger dies have a smaller heat flux and
hence better performance. Smaller dies tend to be cheaper,
though.
a) PBGA package (plastic) b) ceramic flip chip
Effect of Die Power Level
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As power levels go up, so do surface temperatures.
This increases natural convection and radiation,
decreasing qJA
Reporting Requirement Examples
Reporting Requirement Examples
Reference
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Jedec the Standards Resource for the World Semiconductor Industry (October 2006). http://www.jedec.org
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Jedec Standard JESD 22-A103C High Temperature Storage Temperature . Retrieved October 2006.
http://www.jedec.org/download/search/22a103c.pdf.
Jedec Standard JESD51-12 Guidelines for Reporting and Using Electronic Package Thermal Information.
Retreived October 2006. www.jedec.org.
Wikipedia the Free Encyclopedia(October 2006). Jedec. Retrieved October 2006.
http://en.wikipedia.org/wiki/JEDEC .