RMPA0951AT Ver la hoja de datos (PDF) - Fairchild Semiconductor
Número de pieza
componentes Descripción
Fabricante
RMPA0951AT Datasheet PDF : 11 Pages
| |||
Application Information
Precautions to Avoid Permanent Device Damage:
• Cleanliness: Observe proper handling procedures to
ensure clean devices and PCBs. Devices should remain
in their original packaging until component placement to
ensure no contamination or damage to RF, DC & ground
contact areas.
• Device Cleaning: Standard board cleaning techniques
should not present device problems provided that the
boards are properly dried to remove solvents or water
residues.
• Static Sensitivity: Follow ESD precautions to protect
against ESD damage:
– A properly grounded static-dissipative surface on
which to place devices.
– Static-dissipative floor or mat.
– A properly grounded conductive wrist strap for each
person to wear while handling devices.
– General Handling: Handle the package on the top
with a vacuum collet or along the edges with a sharp
pair of bent tweezers. Avoiding damaging the RF, DC,
& ground contacts on the package bottom. Do not
apply excessive pressure to the top of the lid.
– Device Storage: Devices are supplied in heat-sealed,
moisture-barrier bags. In this condition, devices are
protected and require no special storage conditions.
Once the sealed bag has been opened, devices
should be stored in a dry nitrogen environment.
Device Usage:
Fairchild recommends the following procedures prior to
assembly.
• Dry-bake devices at 125°C for 24 hours minimum. Note:
The shipping trays cannot withstand 125°C baking
temperature.
• Assemble the dry-baked devices within 7 days of
removal from the oven.
• During the 7-day period, the devices must be stored in an
environment of less than 60% relative humidity and a
maximum temperature of 30°C
• If the 7-day period or the environmental conditions have
been exceeded, then the dry-bake procedure must be
repeated.
Solder Materials & Temperature Profile:
Reflow soldering is the preferred method of SMT
attachment. Hand soldering is not recommended.
Reflow Profile
• Ramp-up: During this stage the solvents are evaporated
from the solder paste. Care should be taken to prevent
rapid oxidation (or paste slump) and solder bursts
caused by violent solvent out-gassing. A typical heating
rate is 1 - 2°C/sec.
• Pre-heat/soak: The soak temperature stage serves two
purposes; the flux is activated and the board and devices
achieve a uniform temperature. The recommended soak
condition is: 120 -150 seconds at 150°C.
• Reflow Zone: If the temperature is too high, then devices
may be damaged by mechanical stress due to thermal
mismatch or there may be problems due to excessive
solder oxidation. Excessive time at temperature can
enhance the formation of inter-metallic compounds at
the lead/board interface and may lead to early
mechanical failure of the joint. Reflow must occur prior to
the flux being completely driven off. The duration of peak
reflow temperature should not exceed 10 seconds.
Maximum soldering temperatures should be in the range
215 -220°C, with a maximum limit of 225°C.
• Cooling Zone: Steep thermal gradients may give rise to
excessive thermal shock. However, rapid cooling
promotes a finer grain structure and a more crack-
resistant solder joint. Figure 4 indicates the
recommended soldering profile.
Solder Joint Characteristics:
Proper operation of this device depends on a reliable void-
free attachment of the heatsink to the PWB. The solder joint
should be 95% void-free and be a consistent thickness.
Rework Considerations:
Rework of a device attached to a board is limited to reflow
of the solder with a heat gun. The device should not be
subjected to more than 225°C and reflow solder in the
molten state for more than 5 seconds. No more than 2
rework operations should be performed.
©2004 Fairchild Semiconductor Corporation
RMPA0951AT Rev. D
Share Link: 