Microchip Technology PRO MATE II, Руководство пользователя

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1999 Microchip Technology Inc. DS30243H-page 13
Chapter 1. Socket Modules
1.4 Socket Life Expectancy and Cleaning
Procedures
Microchip uses socket modules from several manufacturers. Table 1.3 gives
the expected life (in number of automatic insertions) and cleaning method for
each socket module as reported by the manufacturer.
1.4.1 Manufacturer
Look at the socket module to determine the name of the manufacturer. The
Yamaichi socket is not labeled; identify a Yamaichi socket by looking for the
letters IC51– (as the prefix to a part number) on the socket.
1.4.2 Insertions
The expected life for manual insertions has been found to be less than the
manufacturer’s reported number. The number of manual insertions depends
on the socket condition and how often the socket is cleaned.
Careless insertions or dirty socket conditions can bring the number of
insertions down to less than 5,000. Cleanliness and care in inserting devices
into a socket are most important with surface mount devices as the socket
contactors must remain planar to function properly.
Any bent or nonplanar contacts will result in a failure. Nonplanar socket
module contacts occur earlier in the life of a socket module when devices are
inserted manually into a socket module. Early contact failure from manual
insertions is due to the nonrepeatability of the manual insertion method.
Therefore, the listed number of insertions may not be reached for sockets
where devices are inserted manually. No good method exists to ensure that
the contacts are planar.
Table: 1.3 Socket Life Expectancy and Cleaning Method
Manufacturer Insertions Cleaning Method
Aries (28 pin) 10,000 #2
AMP (18 pin) 25,000 #2
3M Textool 10,000 #1
AMP (Dip) 25,000 #2
3M Textool (SOIC) 10,000 #1
Aries 10,000 #2
Yamaichi 25,000 #1