Intel Pentium 4 Processor 478-Pin Socket (mPGA478) Design Guidelines

Intel® Pentium® 4 Processor 478-Pin Socket (mPGA478)
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5. Environmental Requirements
Design, including materials, shall be consistent with the manufacture of units that meet the following
environmental reference points.
The reliability targets in this section are based on the expected field use environment for a desktop product.
The test sequence for new sockets will be developed using the knowledge-based reliability evaluation
methodology, which is acceleration factor dependent. A simplified process flow of this methodology can be
seen in Figure 5-1 (
below).
Establish the
market/expected use
environment for the
technology
Develop Speculative
stress conditions based on
historical data, content
experts, and literature
search
Perform stressing to
validate accelerated
stressing assumptions and
determine acceleration
factors
Freeze stressing
requirements and perform
additional data turns
Figure 5-1. Flow chart of Knowledge-based Reliability Evaluation Methodology
A detailed description of this methodology can be found at:
http://developer.intel.com/design/packtech
The use environment expectations assumed are for desktop processors, based on an expected life of 7 to 10
years, are listed in Table 5-1 (
below). The target failure rates are <1% at 7 years and <3% at 10 years.
Table 5-1. Use conditions environment
Use Environment Speculative Stress Condition 7 year life
expectation
10 year life
expectation
Slow small internal gradient changes due to external
ambient (temperature cycle or externally heated)
Temperature Cycle 1500 cycles with a
mean ∆T = 40°C
2150 cycles with a
mean ∆T = 40°C
High ambient moisture during low-power state
(operating voltage)-
THB / HAST 62,000 hrs at 30°C,
8%RH
89,000 hrs at 30°C,
85%RH
High Operating temperature and short duration high
temperature exposures
BAKE 62,000 hrs at Tjmax 89,000 hrs at Tjmax