M55302/78-02 Amphenol, M55302/78-02 Datasheet - Page 30
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M55302/78-02
Manufacturer Part Number
M55302/78-02
Description
Board to Board / Mezzanine Connectors POLARIZING KEY
Manufacturer
Amphenol
Type
Polarization Keyr
Specifications of M55302/78-02
Operating Temp Range
-65C to 125C
Product Type
Accessories
Lead Free Status / RoHS Status
Supplier Unconfirmed
Low Mating Force Connector Installation
BRUSH CONNECTORS USER APPLICATION
INFORMATION
The Brush B
mating force device designed to provide a multiplicity or highly
redundant number of contact sites for high density, high
performance applications. Contact resistance is stable and low,
approximately 1/3 lower than the most widely available contem-
porary two piece printed circuit card connector type. To maxi-
mize the B
potential reliability, several guidelines should be followed.
Ideally, connectors should be fully mated and not used as a
packaging system tolerance absorber. Full mating occurs when
the two molded thermoplastic contact housings (connector
bodies) touch, plug skirt to receptacle shoulder over the entire
length of the connector. However, manufacturing tolerances and
user installation procedures must be considered and can be
expected to prevent the “ideal” situation.
Connector bodies were intentionally designed to be non-rigid as
permanent flexibility is necessary to allow compliance to user
printed circuit cards, fixtures and card cages. Vibration and
shock exposure, thermal excursions, contact repairability, and
differential expansion characteristics further dictate the desir-
ability of flexible connectors.
Amphenol drawing call-outs of part flatness to a 0.010 inch FIM
(Total Indicator Reading - Full Indicator Movement) over the
mating surface length is to be interpreted as in an “as used”
condition. Rigid mounting of Mother Board (plug) parts to
frames, multi-layer printed circuit boards or back panels should
consider the need for the 0.010 inch maximum condition after
soldering or solderless wrapping procedures.
Normal Mother Board parts in an unrestrained, unused condition
may exceed the “as used” 0.010 inch reading at normal ambient
or storage environments. Thermal cycling may further aggravate
or adjust the condition. These parts present a profile from flat to
a “smile” appearance when viewed from the side with the mating
surface uppermost. (For example, see photo above). Normal
positioning of this part on the Mother Board with slight restraint
through use of mounting hardware or standard mounting bolts
will automatically allow part compliance to the flatness condition
of the board. Slight restraint is urged to allow for differential
thermal expansion compensation during preheating and
soldering operations. Final torquing or permanent fastening
should be effected after cool down and thermal neutralization.
Normal solderless wrapping procedures could ignore the
differential expansion consideration.
Daughter Board connectors present the same flat to “smile”
profile in a free state with the mating surface downward. The
relief shelf can be used as a reference or guide when used with
a straight edged Daughter Board or printed circuit board “page”.
Once proper positioning is verified and contact tails are solder
fixed to the plated through holes, straightness will be perma-
nently retained.
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connector capability and assure the greatest
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connector is a highly sophisticated, innovative low
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During usage and when mated the worst case condition of the
“as used” 0.010 inch maximum reading of both the plug and
receptacle could cause a maximum gap between plug and
receptacle moldings of 0.020 inch. This condition is well within
the B
effective electrical contact engagement has greater than a
100% safety factor. Users are urged to monitor the quality of
connector installation to optimize the mating of connectors.
Input/Output connectors also normally exhibit a flat to “smile”
profile with the mating surface downward. This “smile” condition
self corrects once mated with the Mother Board counterpart and
accessory locking screws are fastened. Again, checking for the
0.020 inch maximum gap is urged as a quality control monitor of
user application techniques.
Amphenol has attempted to design in the ultimate for connector
compliancy and self-correction during normal user installation
procedures. The connector capabilities and inherent reliability
rely in part on practical user procedures and application
considerations. Refer to pages 27 - 29 for other installation
instructions. And, refer to page 2 for correct mating of low
mating force connectors. Amphenol board level engineers and
product specialists are available to assist the user with applica-
tion recommendations and processing guidance. Give us a call
at 607-563-5011 and ask for board level technical assistance if
further information is needed.
Users are urged to monitor the quality of connector installation
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product mated performance goals as our minimum
DAUGHTER BOARD AND MOTHER BOARD
to optimize the mating of connectors.
FULLY MATED CONDITION