The two lids shown here are from the same socket manufacturer (Enplas) and appear the same. However, testing and examination shows that they are substantially different in ESD performance. Data courtesy of Actel Corporation.
FIELD READINGS ON TEST SOCKET LIDS
Lids as Received
ESD Unfriendly ESD Friendly 1 3600V+ <15V 2 7100V+ <15V 3 3400V+ <15V 4 2400V+ <15V 5 5400V+ <15V 6 5300V+ <15V 7 1900V+ <15V
NASA (Materials Department) Lid Evaluation.
ESD Unfriendly ESD Friendly Point to Point Resistance (ohms) 1 x 1013 4.4 x 106 Conclusion (ANSI/ESD S541-2003) Insulative Static Dissipative
Note: At the time of this writing, there is no known way to determine the composition of the lid by visual inspection. I have submitted some suggestions to make the two lids visually identifiable and have distinct part numbers.
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Last Revised: February 03, 2010
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