![]() |
|||||||||||||||||||
|
Vibration Tests - Mil-Std-883 Methods 2005 and 2007
Vibration Tests are tests performed to determine the effects of mechanical vibration within a specified frequency range on semiconductor devices. There are two military standards that are widely used for this purpose: 1) the Vibration Fatigue Test, as defined by Mil-Std-993 Method 2005; and 2) the Variable Frequency Vibration Test, as defined by Mil-Std-883 Method 2007. Both vibration tests are similar in many aspects, although they are intended to uncover different types of vibration-related failures.
The vibration fatigue test (Method 2005) requires a testing apparatus that is capable of providing sustained vibration within the specified levels, and has the necessary optical and electrical equipment needed to perform post-test measurements. In this test, the sample is firmly fastened on the vibration platform with its leads adequately secured. The sample is then subjected to a simple harmonic vibration that has a constant amplitude having a peak acceleration corresponding to the specified test condition. The vibration shall be performed for 32+/-8 hours minimum in each of the X-, Y-, and Z- orientations, for a total of 96 hours minimum. The test conditions applicable for this test are shown in Table 1.
Table 1. Test Conditions for the Vibration Fatigue Test per Mil-Std-883 Method 2005
The variable frequency vibration test (Method 2007) requires a testing apparatus that is capable of providing the required variable frequency vibration at the specified levels, the necessary optical and electrical equipment needed to perform post-test measurements. In this test, the sample is firmly fastened on the vibration platform with its leads adequately secured. The sample is then subjected to a simple harmonic vibration that has either a peak-to-peak amplitude of 0.06 inch +/- 10% or a peak acceleration of the specified test condition.
The vibration frequency shall then be varied approximately logarithmically between 20 and 2,000 Hz. The entire frequency range of 20-2000 Hz and the return to 20 Hz must be traversed in not less than 4 minutes. This cycle shall be performed 4 times in each of the orientations X, Y, and Z, for a total of 12 times. The test conditions applicable for this test are shown in Table 2.
Table 2. Test Conditions for the Variable Frequency Vibration Test per Mil-Std-883 Method 2007
After either vibration test has been completed, external visual inspection of the case, leads, and seals shall be performed at 10 X to 20 X. The marking shall also be inspected with or without magnification, but with the magnification no greater than 3 X. An illegible mark and/or any evidence of damage to the case, leads, or seals after the stress test shall be considered a failure. Additional specified measurements may also be done after vibration testing.
Reference: Mil-Std-883 Method 2005; Mil-Std-883 Method 2007
Reliability Tests: Autoclave Test or PCT; Temperature Cycling; Thermal Shock; THB; HAST; HTOL; LTOL; HTS; Solder Heat Resistance Test (SHRT);
See Also: Reliability Engineering; Reliability Modeling; Qualification Process; Failure Analysis; Package Failures; Die Failures
Copyright © 2001-2005 www.SiliconFarEast.com. All Rights Reserved. |