User Manual

Reliability Demonstration Report
MaxBotix
®
Inc.
Document Release: 05/12/2010, pg. 8 of 10
10
0
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v1.1b • 07/2009 • Copyright 2005-2010
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4.3 Activation Energies of Integrated Circuit Components
For the purposes of our calculations an activation value of 0.53 eV was used. This
aggrees with the rule of thumb of doubling the equivalent product usage hours for every
10°C above the normal operational temperature. For additional information on the
reliability of electroninc components reference MIL-HDBK-217.
4.4 Acceleration Factor Calculation (Operational Life)
The Arrhenius equation below is used to model the relation between increased
temperature and the acceleration of the aging of a product as compared to its normal
operational temperature.














−=
ts
f
TTk
Ea
eA
11
^
A
f
= acceleration factor
Ea = activation energy in electon-volts (eV) = 0.53 eV
k = Boltzmann’s constant = 8.617 x 10
-5
eV/T
k
T
s
= Temperature of normal operation, in degrees Kelvin = 318°K (45°C)
T
t
= Temperature of operation during test, in degrees Kelvin = 358°K (85°C)
T
k
= Kelvin Temperature
e = 2.71828 (mathematical constant)
This equation yeilds an acceleration factor of 8.00.
Failure Mode Activation energy in eV
Oxide Breakdown 0.3 - 0.5 eV
Corrosion 0.3 - 0.5 eV
Electo-migration 0.45 - 1.0 eV
Ionic Migration 0.6 - 1.4 eV
Assembly Defects 0.5 - 0.7 eV